Ricardo G. Durán, Enrique Otárola and Abner J. Salgado
Math. Comp. 89 (2020), 1581-1603.
Abstract, references and article information

The proptech startup wanted to democratise investment in prime real estate projects through crowdfunding, but government regulations have limited its reach to high net worth individuals

While coordinated action is urgently needed, should we be racing to download everything that promises a solution?

The relationship wellness app is seeing a significant uptick in interest as couples are locked down together during the COVID-19 pandemic

Huai-Liang Chang and Mu-lin Li
Trans. Amer. Math. Soc. 373 (2020), 3669-3691.
Abstract, references and article information

Mahbub Alam and Anish Ghosh
Trans. Amer. Math. Soc. 373 (2020), 3357-3374.
Abstract, references and article information

Kathrin Bringmann, Matthew Krauel and Michael Tuite
Trans. Amer. Math. Soc. 373 (2020), 3261-3293.
Abstract, references and article information

Robert Grizzard and Jeffrey D. Vaaler
Trans. Amer. Math. Soc. 373 (2020), 3235-3259.
Abstract, references and article information

Kamen G. Ivanov and Pencho Petrushev
Trans. Amer. Math. Soc. 373 (2020), 3117-3176.
Abstract, references and article information

V. M. Radchenko and N. O. Stefans’ka
Theor. Probability and Math. Statist. 99 (2020), 229-238.
Abstract, references and article information

S. V. Bodnarchuk and O. M. Kulyk
Theor. Probability and Math. Statist. 99 (2020), 53-65.
Abstract, references and article information

Alyson Bittner
Proc. Amer. Math. Soc. 148 (2020), 2683-2693.
Abstract, references and article information

Alexander J. Rasmussen
Proc. Amer. Math. Soc. 148 (2020), 2345-2357.
Abstract, references and article information

The Government today announced the establishment of a LawTech Fund to help law firms and barristers' chambers procure and upgrade information technology (IT) systems and arrange lawtech training courses for their staff.

In a statement, the Department of Justice said the LawTech Fund, established under the Anti-epidemic Fund, will be open for applications from April 28 and cater to small and medium-size law firms as well as barristers’ chambers.

Applications will be accepted for two months and those eligible can receive a reimbursement of up to $50,000.

The Law Society of Hong Kong and the Hong Kong Bar Association will establish a joint committee to assess the applications and arrange funding disbursement.

More than 60% of law firms and 50% of barristers' chambers in Hong Kong are expected to benefit from the funding.

As for funding eligibility, law firms or chambers must have five or fewer practising lawyers as at April 8 and at the time of granting the subsidy.

The subsidies must be used for procuring and upgrading IT systems, including but not confined to video-conferencing facilities. The lawtech training that is to receive the subsidy must be recognised and approved by the joint committee.

The application form and guidance notes are available at the homepages of the Law Society and the Bar Association.

The Secretary for Justice has given an outline of the fund and discussed lawtech in her blog.

The city's annual Jazz Marathon will be held on April 25.

The all-day music event will see artists from France, India, Italy, Japan, the Mainland, Russia and the US collaborate with local musicians to create a borderless jazz soundscape.

The Day Marathon Concert will be held from 2.30pm to 6pm while the Night Marathon Concert will be held from 7.15pm to 10.45pm.

 
Ahead of the concerts, jazz workshops with the artists will be held on April 24.

Presented by the Leisure & Cultural Services Department, the events will be held at Queen Elizabeth Stadium in Wan Chai.

Tickets are available at URBTIX.

Click here for details.

An Ap Lei Chau site in the 2020-21 Land Sale Programme will be sold by public tender, the Lands Department announced today.

Ap Lei Chau Inland Lot No. 137 at Ap Lei Chau Praya Road is designated for non-industrial purposes, excluding godown, hotel and petrol filling station.

It has a site area of about 1,128.8 sq m with a minimum gross floor area of 4,921 sq m.

The maximum gross floor area for private residential purposes is 8,201.6 sq m, while that for other designated purposes is computed according to the relevant special sale condition.

The tender invitation for the lot will open on April 24 and close on May 22.

More than 40,000 new niches at two columbaria in Tuen Mun and Fanling will open for applications from May 11, the Food & Environmental Hygiene Department announced today.

Tsang Tsui Columbarium in Tuen Mun will provide 22,680 standard niches and 220 large niches, while Wo Hop Shek Columbarium in Fanling will provide 21,720 standard niches and 330 large niches for application.

The department said applicants should only file one application form to apply for either a large or standard niche for the same deceased person.

It said applicants have to fill in the particulars of at least three deceased people when applying for a large niche.

Since the type and number of niches available in the two columbaria are different, the chance of successful allocation varies, the department added.

The application deadline is June 10.

Click here for details.

The Buildings Department approved 13 building plans in February - four on Hong Kong Island, one in Kowloon and eight in the New Territories.

Of the approved plans, nine were for apartment and apartment-commercial developments, one was for commercial development, one was for factory and industrial developments, and two were for community services developments.

Consent was given for works to start on two building projects, which will provide 77,942 sq m of gross floor area for non-domestic use.

The department also issued 14 occupation permits - four on Hong Kong Island, one in Kowloon and nine in the New Territories.

Buildings certified for occupation have 149,306 sq m of gross floor area for domestic use involving 2,912 units, and 67,594 sq m for non-domestic use.

The declared cost of new buildings completed in the month was $3.7 billion.

(To watch the full press conference with sign language interpretation, click here.)

The Government is confident that the Hong Kong Diploma of Secondary Education (DSE) Examination could be held on April 24.

Secretary for Education Kevin Yeung made the statement when explaining the arrangements for the DSE examination at a press conference today.

Mr Yeung said the Government understands that some DSE candidates are concerned about their safety.

He said measures will be taken to make sure that examination venues will be as safe as possible.

Exam candidates will have to wear masks, which have already been distributed, before entering the examination centres. Hand sanitisers will also be given to them.

If a candidate has a fever or upper respiratory tract symptoms, they will not be allowed to take the exam.

Additionally, more classrooms will be turned into examination centres and desks will be separated by at least 1.8m in most centres.

Mr Yeung said: “We are now confident that the exam could be held on April 24.

“We believe that with everyone’s effort and hopefully with the support of the community in trying to control the spread of the disease, we will be able to complete the DSE exam by the end of May.”

The Chief Executive has reappointed Frederick Ma as Chairman of the Education University of Hong Kong (EdUHK) Council from April 25 to December 31, the Government announced today.

Secretary for Education Kevin Yeung thanked Mr Ma for accepting the reappointment, saying that under his leadership, EdUHK continues to focus on educational research, development and innovation and promoting and supporting the development of teacher education in Hong Kong by nurturing outstanding and committed educators and professionals.

Mr Ma cannot accept a three-year term up until 2023 due to personal reasons. In the meantime, the Government will identify a suitable candidate for the chairmanship of the EdUHK Council.

Jimmy Doumit
Feb 1, 2016; 29:14-19
From Research to Practice

Brenna Cholerton
Nov 1, 2016; 29:210-219
From Research to Practice

Ryan A. Ristau
Nov 1, 2013; 26:211-215
From Research to Practice

Katherine S. O’Neal
Nov 1, 2016; 29:249-252
Pharmacy and Therapeutics

The Housing Authority’s Commercial Properties Committee today approved the extension of rent concessions to over 8,300 non-domestic tenants or licensees for six months from April 1 to September 30.

The authority had earlier granted a 50% rent concession to its eligible retail and factory tenants for six months from April 1.

Under the extension, their rent concession will be increased to 75% over the same period with retrospective effect from April 1. The rent concession does not include rates and air-conditioning charges.

The authority said such further measures are to support the Government's new series of measures announced in early April to relieve the financial burden of individuals and businesses.

A total of 2,450 retail and 3,300 factory tenants will benefit from the approved increase in the rent concession.

The 75% rent concession will also be extended to cover tenants and licensees of bus kiosks and most advertising signboards, as well as car park users for the monthly parking of commercial vehicles.

About 40 tenancies for bus kiosks, 80 advertising signboards and about 2,500 car park users stand to benefit from the concession.

Tenants of premises in the authority's properties which are required to be closed under relevant regulations or the Government's directions, may also apply to the authority for a 100% rent concession for the period during which they are required to be closed.

The authority added that the approved measures will be implemented as soon as possible. For rent and licence fees already paid for the months of April and May, arrangements will be made for offsetting in the payment for subsequent months.

The committee has approved three rounds of rent concessions since last September. Together with this round, the total rent and licence fees foregone by the authority is estimated to reach more than $1 billion.

The Government will launch the Subsidy Scheme for Beauty Parlours, Massage Establishments & Party Rooms under the second round of the Anti-epidemic Fund on May 11.

A sum of $1.1 billion has been earmarked for the scheme, which is expected to benefit 12,400 beauty parlours and massage establishments as well as 500 party rooms.

The subsidy is expected to be disbursed from late this month.

Under the scheme, each eligible beauty parlour or massage establishment will receive a one-off tiered subsidy of $30,000, $60,000 or $100,000, depending on its number of workers.

Each eligible party room will receive a one-off subsidy of $40,000.

Applications will only be accepted online. The application deadline is May 17.

The scheme also covers premises which are operated by social enterprises.

For premises with business registration, social enterprise operators should file their applications through the online application system.

Those without business registration should directly approach the Hong Kong Council of Social Service at 2864 2993 or by email to obtain its certification and submit their applications.

Call 1836 188 or send an email for enquiries.

Hong Kong Exchanges & Clearing Limited (HKEx) today announced that Charles Li will not seek reappointment as Chief Executive at the end of his current contract in October 2021.

The Government said it respected Mr Li's decision and expressed deep appreciation for his exemplary contribution to the development of the financial market during his tenure as HKEx Chief Executive in the past decade.

Since taking the helm in January 2010, he has led HKEx and Hong Kong’s capital market in achieving important breakthroughs one after another.

The vibrancy and growth that Mr Li has brought to Hong Kong in the capital market helps reinforce the status of Hong Kong as a leading international financial centre.

Financial Secretary Paul Chan said: "Thanks to his vision and leadership, Mr Li has laid a solid and strong foundation for our stock market, rendering Hong Kong the largest IPO market in the world for seven times in the past 11 years.

"He has been instrumental in the successful launch of mutual market access programmes between Hong Kong and the Mainland, notably the Shanghai-Hong Kong Stock Connect in 2014, which was expanded to include Shenzhen-Hong Kong Stock Connect in 2016 and Bond Connect in 2017.

"He also played a pivotal role in the launch of new listing regime in Hong Kong, the enhanced internationalisation of HKEx and its international visibility. These are all important achievements of HKEx in the past few years under Mr Li’s able leadership."

Mr Chan added that the Government is confident the HKEx board will continue to ensure the success of HKEx in the years to come.

(Fundação de Amparo à Pesquisa do Estado de São Paulo) Thanks to its magnetic properties, the material -- zinc-doped manganese chromite -- can be used in a range of products, from gas sensors to data storage devices.

(University of Montreal) A chemistry professor at Université de Montréal has developed a new test using gold nanoparticles to establish the flavour profile of maple syrup and help producers evaluate its quality.

(University of Illinois Grainger College of Engineering) Three Nick Holonyak Jr., Micro and Nanotechnology Lab (HMNTL) faculty members received NSF Rapid Response Research (RAPID) program grants, all of which aim to shorten the amount of time it takes to process a COVID-19 test with less false negatives. Current tests can take as long as five days for results to be.

More than 8,200 applications for the Anti-epidemic Support Scheme for Property Management Sector (ASPM) have been received, with over 3,850 approved, the Government announced today.

The approved applications involve subsidies of more than $140 million and will benefit around 22,000 building blocks and about 35,750 frontline property management workers.

Launched under the Anti-epidemic Fund, the ASPM provides subsidies to owners' organisations or property management companies of eligible buildings to provide hardship allowance to frontline property management workers.

It also provides the Anti-epidemic Cleansing Subsidy to owners' organisations or property management companies.

The scheme’s first phase covers private residential and composite buildings, while its second phase covers industrial and commercial buildings.

The ASPM is still open for applications and continues to disburse subsidies.

Contact the Property Management Services Authority at 3696 1156 or 3696 1166, or visit its website for details.

Prevention of aberrant cutaneous wound repair and appropriate regeneration of an intact and functional integument require the coordinated timing of fibroblast and keratinocyte migration. Here, we identified a mechanism whereby opposing cell-specific motogenic functions of a multifunctional intracellular and extracellular protein, the receptor for hyaluronan-mediated motility (RHAMM), coordinates fibroblast and keratinocyte migration speed and ensures appropriate timing of excisional wound closure. We found that, unlike in WT mice, in Rhamm-null mice, keratinocyte migration initiates prematurely in the excisional wounds, resulting in wounds that have re-surfaced before the formation of normal granulation tissue, leading to a defective epidermal architecture. We also noted aberrant keratinocyte and fibroblast migration in the Rhamm-null mice, indicating that RHAMM suppresses keratinocyte motility but increases fibroblast motility. This cell context–dependent effect resulted from cell-specific regulation of extracellular signal-regulated kinase 1/2 (ERK1/2) activation and expression of a RHAMM target gene encoding matrix metalloprotease 9 (MMP-9). In fibroblasts, RHAMM promoted ERK1/2 activation and MMP-9 expression, whereas in keratinocytes, RHAMM suppressed these activities. In keratinocytes, loss of RHAMM function or expression promoted epidermal growth factor receptor–regulated MMP-9 expression via ERK1/2, which resulted in cleavage of the ectodomain of the RHAMM partner protein CD44 and thereby increased keratinocyte motility. These results identify RHAMM as a key factor that integrates the timing of wound repair by controlling cell migration.

Heterotrimeric G proteins are the core upstream elements that transduce and amplify the cellular signals from G protein–coupled receptors (GPCRs) to intracellular effectors. GPCRs are the largest family of membrane proteins encoded in the human genome and are the targets of about one-third of prescription medicines. However, to date, no single therapeutic agent exerts its effects via perturbing heterotrimeric G protein function, despite a plethora of evidence linking G protein malfunction to human disease. Several recent studies have brought to light that the Gq family–specific inhibitor FR900359 (FR) is unexpectedly efficacious in silencing the signaling of Gq oncoproteins, mutant Gq variants that mostly exist in the active state. These data not only raise the hope that researchers working in drug discovery may be able to potentially strike Gq oncoproteins from the list of undruggable targets, but also raise questions as to how FR achieves its therapeutic effect. Here, we place emphasis on these recent studies and explain why they expand our pharmacological armamentarium for targeting Gq protein oncogenes as well as broaden our mechanistic understanding of Gq protein oncogene function. We also highlight how this novel insight impacts the significance and utility of using G(q) proteins as targets in drug discovery efforts.

VOLUME 295 (2020) PAGES 3285–3300An incorrect graph was used in Fig. 5C. This error has now been corrected. Additionally, some of the statistics reported in the legend and text referring to Fig. 5C were incorrect. The F statistics for Fig. 5C should state Fken(3,16) = 7.454, p < 0.01; FCCCP(1,16) = 102.9, p < 0.0001; Finteraction(3,16) = 7.480, p < 0.01. This correction does not affect the results or conclusions of this work.jbc;295/17/5835/F5F1F5Figure 5C.

Actinobacillus pleuropneumoniae (App) is the etiological agent of acute porcine pneumonia and responsible for severe economic losses worldwide. The capsule polymer of App serotype 1 (App1) consists of [4)-GlcNAc-β(1,6)-Gal-α-1-(PO4-] repeating units that are O-acetylated at O-6 of the GlcNAc. It is a major virulence factor and was used in previous studies in the successful generation of an experimental glycoconjugate vaccine. However, the application of glycoconjugate vaccines in the animal health sector is limited, presumably because of the high costs associated with harvesting the polymer from pathogen culture. Consequently, here we exploited the capsule polymerase Cps1B of App1 as an in vitro synthesis tool and an alternative for capsule polymer provision. Cps1B consists of two catalytic domains, as well as a domain rich in tetratricopeptide repeats (TPRs). We compared the elongation mechanism of Cps1B with that of a ΔTPR truncation (Cps1B-ΔTPR). Interestingly, the product profiles displayed by Cps1B suggested processive elongation of the nascent polymer, whereas Cps1B-ΔTPR appeared to work in a more distributive manner. The dispersity of the synthesized products could be reduced by generating single-action transferases and immobilizing them on individual columns, separating the two catalytic activities. Furthermore, we identified the O-acetyltransferase Cps1D of App1 and used it to modify the polymers produced by Cps1B. Two-dimensional NMR analyses of the products revealed O-acetylation levels identical to those of polymer harvested from App1 culture supernatants. In conclusion, we have established a protocol for the pathogen-free in vitro synthesis of tailored, nature-identical App1 capsule polymers.

Fatty acid transport protein 2 (FATP2) is highly expressed in the liver, small intestine, and kidney, where it functions in both the transport of exogenous long-chain fatty acids and the activation of very-long-chain fatty acids. Here, using a murine model, we investigated the phenotypic impacts of deleting FATP2, followed by a transcriptomic analysis using unbiased RNA-Seq to identify concomitant changes in the liver transcriptome. WT and FATP2-null (Fatp2−/−) mice (5 weeks) were maintained on a standard chow diet for 6 weeks. The Fatp2−/− mice had reduced weight gain, lowered serum triglyceride, and increased serum cholesterol levels and attenuated dietary fatty acid absorption. Transcriptomic analysis of the liver revealed 258 differentially expressed genes in male Fatp2−/− mice and a total of 91 in female Fatp2−/− mice. These genes mapped to the following gene ontology categories: fatty acid degradation, peroxisome biogenesis, fatty acid synthesis, and retinol and arachidonic acid metabolism. Targeted RT-quantitative PCR verified the altered expression of selected genes. Of note, most of the genes with increased expression were known to be regulated by peroxisome proliferator–activated receptor α (PPARα), suggesting that FATP2 activity is linked to a PPARα-specific proximal ligand. Targeted metabolomic experiments in the Fatp2−/− liver revealed increases of total C16:0, C16:1, and C18:1 fatty acids; increases in lipoxin A4 and prostaglandin J2; and a decrease in 20-hydroxyeicosatetraenoic acid. We conclude that the expression of FATP2 in the liver broadly affects the metabolic landscape through PPARα, indicating that FATP2 provides an important role in liver lipid metabolism through its transport or activation activities.

Lens proteins become increasingly cross-linked through nondisulfide linkages during aging and cataract formation. One mechanism that has been implicated in this cross-linking is glycation through formation of advanced glycation end products (AGEs). Here, we found an age-associated increase in stiffness in human lenses that was directly correlated with levels of protein–cross-linking AGEs. α-Crystallin in the lens binds to other proteins and prevents their denaturation and aggregation through its chaperone-like activity. Using a FRET-based assay, we examined the stability of the αA-crystallin–γD-crystallin complex for up to 12 days and observed that this complex is stable in PBS and upon incubation with human lens–epithelial cell lysate or lens homogenate. Addition of 2 mm ATP to the lysate or homogenate did not decrease the stability of the complex. We also generated complexes of human αA-crystallin or αB-crystallin with alcohol dehydrogenase or citrate synthase by applying thermal stress. Upon glycation under physiological conditions, the chaperone–client complexes underwent greater extents of cross-linking than did uncomplexed protein mixtures. LC-MS/MS analyses revealed that the levels of cross-linking AGEs were significantly higher in the glycated chaperone–client complexes than in glycated but uncomplexed protein mixtures. Mouse lenses subjected to thermal stress followed by glycation lost resilience more extensively than lenses subjected to thermal stress or glycation alone, and this loss was accompanied by higher protein cross-linking and higher cross-linking AGE levels. These results uncover a protein cross-linking mechanism in the lens and suggest that AGE-mediated cross-linking of α-crystallin–client complexes could contribute to lens aging and presbyopia.

VOLUME 289 (2014) PAGES 30635–30644This article has been withdrawn by Guangnan Chen, Dongkyoo Park, Francis A. Cucinotta, David S. Yu, Xingming Deng, William S. Dynan, Paul W. Doetsch, and Ya Wang. Hongyan Wang, Xiang Wang, Xiangming Zhang, and Xiaobing Tang could not be reached. The last two lanes of the actin immunoblot in Fig. 1A were reused in the last two lanes of the actin immunoblot in Fig. 1C. In Fig. 2A, the γ-H2AX and the merge with DAPI images for no IR treatment do not match. In Fig. 3A, lanes 3 and 4 of the γ-H2AX immunoblot were reused in lanes 7 and 8, and lanes 5 and 6 of the H2A immunoblot were reused in lanes 7 and 8. In Fig. 3B, lanes 5 and 6 of the H2A immunoblot were reused in lanes 7 and 8. In Fig. 3C, lanes 5 and 6 of the γ-H2AX immunoblot were reused in lanes 7 and 8. Additionally, lanes 1 and 2 of the H2A immunoblot were reused in lanes 3 and 4. In Fig. 3D, lanes 1 and 2 of the Mre11 immunoblot from lysates were reused in lanes 4 and 5. In the γ-H2AX immunoblot, lane 3 was reused in lane 7, and lane 4 was reused in lanes 6 and 8. Also in the H2A immunoblot, lanes 1 and 2 were reused in lanes 3 and 4. In Fig. 4B, lanes 2 and 6 of the Mre11 immunoblot from Ogg1−/− cells are the same. In the Ape1...

Although a robust inflammatory response is needed to combat infection, this response must ultimately be terminated to prevent chronic inflammation. One mechanism that terminates inflammatory signaling is the production of alternative mRNA splice forms in the Toll-like receptor (TLR) signaling pathway. Whereas most genes in the TLR pathway encode positive mediators of inflammatory signaling, several, including that encoding the MyD88 signaling adaptor, also produce alternative spliced mRNA isoforms that encode dominant-negative inhibitors of the response. Production of these negatively acting alternatively spliced isoforms is induced by stimulation with the TLR4 agonist lipopolysaccharide (LPS); thus, this alternative pre-mRNA splicing represents a negative feedback loop that terminates TLR signaling and prevents chronic inflammation. In the current study, we investigated the mechanisms regulating the LPS-induced alternative pre-mRNA splicing of the MyD88 transcript in murine macrophages. We found that 1) the induction of the alternatively spliced MyD88 form is due to alternative pre-mRNA splicing and not caused by another RNA regulatory mechanism, 2) MyD88 splicing is regulated by both the MyD88- and TRIF-dependent arms of the TLR signaling pathway, 3) MyD88 splicing is regulated by the NF-κB transcription factor, and 4) NF-κB likely regulates MyD88 alternative pre-mRNA splicing per se rather than regulating splicing indirectly by altering MyD88 transcription. We conclude that alternative splicing of MyD88 may provide a sensitive mechanism that ensures robust termination of inflammation for tissue repair and restoration of normal tissue homeostasis once an infection is controlled.

Bacterial products such as lipopolysaccharides (or endotoxin) cause systemic inflammation, resulting in a substantial global health burden. The onset, progression, and resolution of the inflammatory response to endotoxin are usually tightly controlled to avoid chronic inflammation. Members of the NF-κB family of transcription factors are key drivers of inflammation that activate sets of genes in response to inflammatory signals. Such responses are typically short-lived and can be suppressed by proteins that act post-translationally, such as the SOCS (suppressor of cytokine signaling) family. Less is known about direct transcriptional regulation of these responses, however. Here, using a combination of in vitro approaches and in vivo animal models, we show that endotoxin treatment induced expression of the well-characterized transcriptional repressor Krüppel-like factor 3 (KLF3), which, in turn, directly repressed the expression of the NF-κB family member RELA/p65. We also observed that KLF3-deficient mice were hypersensitive to endotoxin and exhibited elevated levels of circulating Ly6C+ monocytes and macrophage-derived inflammatory cytokines. These findings reveal that KLF3 is a fundamental suppressor that operates as a feedback inhibitor of RELA/p65 and may be important in facilitating the resolution of inflammation.

The formation of translationally inactive 70S dimers (called 100S ribosomes) by hibernation-promoting factor is a widespread survival strategy among bacteria. Ribosome dimerization is thought to be reversible, with the dissociation of the 100S complexes enabling ribosome recycling for participation in new rounds of translation. The precise pathway of 100S ribosome recycling has been unclear. We previously found that the heat-shock GTPase HflX in the human pathogen Staphylococcus aureus is a minor disassembly factor. Cells lacking hflX do not accumulate 100S ribosomes unless they are subjected to heat exposure, suggesting the existence of an alternative pathway during nonstressed conditions. Here, we provide biochemical and genetic evidence that two essential translation factors, ribosome-recycling factor (RRF) and GTPase elongation factor G (EF-G), synergistically split 100S ribosomes in a GTP-dependent but tRNA translocation-independent manner. We found that although HflX and the RRF/EF-G pair are functionally interchangeable, HflX is expressed at low levels and is dispensable under normal growth conditions. The bacterial RRF/EF-G pair was previously known to target only the post-termination 70S complexes; our results reveal a new role in the reversal of ribosome hibernation that is intimately linked to bacterial pathogenesis, persister formation, stress responses, and ribosome integrity.

Coenzyme Q (Qn) is a vital lipid component of the electron transport chain that functions in cellular energy metabolism and as a membrane antioxidant. In the yeast Saccharomyces cerevisiae, coq1–coq9 deletion mutants are respiratory-incompetent, sensitive to lipid peroxidation stress, and unable to synthesize Q6. The yeast coq10 deletion mutant is also respiratory-deficient and sensitive to lipid peroxidation, yet it continues to produce Q6 at an impaired rate. Thus, Coq10 is required for the function of Q6 in respiration and as an antioxidant and is believed to chaperone Q6 from its site of synthesis to the respiratory complexes. In several fungi, Coq10 is encoded as a fusion polypeptide with Coq11, a recently identified protein of unknown function required for efficient Q6 biosynthesis. Because “fused” proteins are often involved in similar biochemical pathways, here we examined the putative functional relationship between Coq10 and Coq11 in yeast. We used plate growth and Seahorse assays and LC-MS/MS analysis to show that COQ11 deletion rescues respiratory deficiency, sensitivity to lipid peroxidation, and decreased Q6 biosynthesis of the coq10Δ mutant. Additionally, immunoblotting indicated that yeast coq11Δ mutants accumulate increased amounts of certain Coq polypeptides and display a stabilized CoQ synthome. These effects suggest that Coq11 modulates Q6 biosynthesis and that its absence increases mitochondrial Q6 content in the coq10Δcoq11Δ double mutant. This augmented mitochondrial Q6 content counteracts the respiratory deficiency and lipid peroxidation sensitivity phenotypes of the coq10Δ mutant. This study further clarifies the intricate connection between Q6 biosynthesis, trafficking, and function in mitochondrial metabolism.

Antibodies are widely used as cancer therapeutics, but their current use is limited by the low number of antigens restricted to cancer cells. A receptor tyrosine kinase, receptor tyrosine kinase-like orphan receptor 2 (ROR2), is normally expressed only during embryogenesis and is tightly down-regulated in postnatal healthy tissues. However, it is up-regulated in a diverse set of hematologic and solid malignancies, thus ROR2 represents a candidate antigen for antibody-based cancer therapy. Here we describe the affinity maturation and humanization of a rabbit mAb that binds human and mouse ROR2 but not human ROR1 or other human cell-surface antigens. Co-crystallization of the parental rabbit mAb in complex with the human ROR2 kringle domain (hROR2-Kr) guided affinity maturation by heavy-chain complementarity-determining region 3 (HCDR3)-focused mutagenesis and selection. The affinity-matured rabbit mAb was then humanized by complementarity-determining region (CDR) grafting and framework fine tuning and again co-crystallized with hROR2-Kr. We show that the affinity-matured and humanized mAb retains strong affinity and specificity to ROR2 and, following conversion to a T cell–engaging bispecific antibody, has potent cytotoxicity toward ROR2-expressing cells. We anticipate that this humanized affinity-matured mAb will find application for antibody-based cancer therapy of ROR2-expressing neoplasms.

The rapid emergence and dissemination of methicillin-resistant Staphylococcus aureus (MRSA) strains poses a major threat to public health. MRSA possesses an arsenal of secreted host-damaging virulence factors that mediate pathogenicity and blunt immune defenses. Panton–Valentine leukocidin (PVL) and α-toxin are exotoxins that create lytic pores in the host cell membrane. They are recognized as being important for the development of invasive MRSA infections and are thus potential targets for antivirulence therapies. Here, we report the high-resolution X-ray crystal structures of both PVL and α-toxin in their soluble, monomeric, and oligomeric membrane-inserted pore states in complex with n-tetradecylphosphocholine (C14PC). The structures revealed two evolutionarily conserved phosphatidylcholine-binding mechanisms and their roles in modulating host cell attachment, oligomer assembly, and membrane perforation. Moreover, we demonstrate that the soluble C14PC compound protects primary human immune cells in vitro against cytolysis by PVL and α-toxin and hence may serve as the basis for the development of an antivirulence agent for managing MRSA infections.