@article {6582, title = {Disruption of DNA methylation-mediated cranial neural crest proliferation and differentiation causes orofacial clefts in mice.}, journal = {Proc Natl Acad Sci U S A}, volume = {121}, year = {2024}, month = {2024 Jan 16}, pages = {e2317668121}, abstract = {

Orofacial clefts of the lip and palate are widely recognized to result from complex gene-environment interactions, but inadequate understanding of environmental risk factors has stymied development of prevention strategies. We interrogated the role of DNA methylation, an environmentally malleable epigenetic mechanism, in orofacial development. Expression of the key DNA methyltransferase enzyme DNMT1 was detected throughout palate morphogenesis in the epithelium and underlying cranial neural crest cell (cNCC) mesenchyme, a highly proliferative multipotent stem cell population that forms orofacial connective tissue. Genetic and pharmacologic manipulations of DNMT activity were then applied to define the tissue- and timing-dependent requirement of DNA methylation in orofacial development. cNCC-specific inactivation targeting initial palate outgrowth resulted in OFCs, while later targeting during palatal shelf elevation and elongation did not. Conditional deletion reduced cNCC proliferation and subsequent differentiation trajectory, resulting in attenuated outgrowth of the palatal shelves and altered development of cNCC-derived skeletal elements. Finally, we found that the cellular mechanisms of cleft pathogenesis observed in vivo can be recapitulated by pharmacologically reducing DNA methylation in multipotent cNCCs cultured in vitro. These findings demonstrate that DNA methylation is a crucial epigenetic regulator of cNCC biology, define a critical period of development in which its disruption directly causes OFCs, and provide opportunities to identify environmental influences that contribute to OFC risk.

}, keywords = {Animals, Cell Proliferation, Cleft Lip, Cleft Palate, DNA Methylation, DNA Modification Methylases, Mice, Neural Crest}, issn = {1091-6490}, doi = {10.1073/pnas.2317668121}, author = {Ulschmid, Caden M and Sun, Miranda R and Jabbarpour, Christopher R and Steward, Austin C and Rivera-Gonz{\'a}lez, Kenneth S and Cao, Jocelyn and Martin, Alexander A and Barnes, Macy and Wicklund, Lorena and Madrid, Andy and Papale, Ligia A and Joseph, Diya B and Vezina, Chad M and Alisch, Reid S and Lipinski, Robert J} } @article {3870, title = {High-affinity binding of celastrol to monomeric α-synuclein mitigates in~vitro aggregation.}, journal = {J Biomol Struct Dyn}, year = {2023}, month = {2023 Feb 06}, pages = {1-11}, abstract = {

α-Synuclein (αSyn) aggregation is associated with Parkinson{\textquoteright}s disease (PD). The region αSyn acts as the nucleation {\textquoteright}master controller{\textquoteright} and αSyn as a {\textquoteright}secondary nucleation site{\textquoteright}. They drive monomeric αSyn to aggregation. Small molecules targeting these motifs are promising for disease-modifying therapy. Using computational techniques, we screened thirty phytochemicals for αSyn binding. The top three compounds were experimentally validated for their binding affinity. Amongst them, celastrol showed high binding affinity. NMR analysis confirmed stable αSyn-celastrol interactions involving several residues in the N-terminus and NAC regions but not in the C-terminal tail. Importantly, celastrol interacted extensively with the key motifs that drive αSyn aggregation. Thioflavin-T assay indicated that celastrol reduced αSyn aggregation. Thus, celastrol holds promise as a potent drug candidate for PD.Communicated by Ramaswamy H. Sarma.

}, issn = {1538-0254}, doi = {10.1080/07391102.2023.2175379}, author = {R, Kavya and Aouti, Snehal and Jos, Sneha and Prasad, Thazhe Kootteri and K N, Kumuda and Unni, Sruthi and Padmanabhan, Balasundaram and Kamariah, Neelagandan and Padavattan, Sivaraman and Mythri, Rajeswara Babu} } @article {2273, title = {Discovery of a body-wide photosensory array that matures in an adult-like animal and mediates eye-brain-independent movement and arousal.}, journal = {Proc Natl Acad Sci U S A}, volume = {118}, year = {2021}, month = {2021 May 18}, abstract = {

The ability to respond to light has profoundly shaped life. Animals with eyes overwhelmingly rely on their visual circuits for mediating light-induced coordinated movements. Building on previously reported behaviors, we report the discovery of an organized, eye-independent (extraocular), body-wide photosensory framework that allows even a head-removed animal to move like an intact animal. Despite possessing sensitive cerebral eyes and a centralized brain that controls most behaviors, head-removed planarians show acute, coordinated ultraviolet-A (UV-A) aversive phototaxis. We find this eye-brain-independent phototaxis is mediated by two noncanonical rhabdomeric opsins, the first known function for this newly classified opsin-clade. We uncover a unique array of dual-opsin-expressing photoreceptor cells that line the periphery of animal body, are proximal to a body-wide nerve net, and mediate UV-A phototaxis by engaging multiple modes of locomotion. Unlike embryonically developing cerebral eyes that are functional when animals hatch, the body-wide photosensory array matures postembryonically in "adult-like animals." Notably, apart from head-removed phototaxis, the body-wide, extraocular sensory organization also impacts physiology of intact animals. Low-dose UV-A, but not visible light (ocular-stimulus), is able to arouse intact worms that have naturally cycled to an inactive/rest-like state. This wavelength selective, low-light arousal of resting animals is noncanonical-opsin dependent but eye independent. Our discovery of an autonomous, multifunctional, late-maturing, organized body-wide photosensory system establishes a paradigm in sensory biology and evolution of light sensing.

}, issn = {1091-6490}, doi = {10.1073/pnas.2021426118}, author = {Shettigar, Nishan and Chakravarthy, Anirudh and Umashankar, Suchitta and Lakshmanan, Vairavan and Palakodeti, Dasaradhi and Gulyani, Akash} } @article {2327, title = {Engineered RNA biosensors enable ultrasensitive SARS-CoV-2 detection in a simple color and luminescence assay.}, journal = {Life Sci Alliance}, volume = {4}, year = {2021}, month = {2021 12}, abstract = {

The continued resurgence of the COVID-19 pandemic with multiple variants underlines the need for diagnostics that are adaptable to the virus. We have developed toehold RNA-based sensors across the SARS-CoV-2 genome for direct and ultrasensitive detection of the virus and its prominent variants. Here, isothermal amplification of a fragment of SARS-CoV-2 RNA coupled with activation of our biosensors leads to a conformational switch in the sensor. This leads to translation of a reporter protein, for example, LacZ or nano-lantern that is easily detected using color/luminescence. By optimizing RNA amplification and biosensor design, we have generated a highly sensitive diagnostic assay that is capable of detecting as low as 100 copies of viral RNA with development of bright color. This is easily visualized by the human eye and quantifiable using spectrophotometry. Finally, this PHAsed NASBA-Translation Optical Method (PHANTOM) using our engineered RNA biosensors efficiently detects viral RNA in patient samples. This work presents a powerful and universally accessible strategy for detecting COVID-19 and variants. This strategy is adaptable to further viral evolution and brings RNA bioengineering center-stage.

}, keywords = {Biosensing Techniques, COVID-19, Humans, Luminescence, Nucleic Acid Amplification Techniques, RNA, RNA, Viral, SARS-CoV-2}, issn = {2575-1077}, doi = {10.26508/lsa.202101213}, author = {Chakravarthy, Anirudh and Nandakumar, Anirudh and George, Geen and Ranganathan, Shyamsundar and Umashankar, Suchitta and Shettigar, Nishan and Palakodeti, Dasaradhi and Gulyani, Akash and Ramesh, Arati} } @article {2323, title = {Genomic characterization and epidemiology of an emerging SARS-CoV-2 variant in Delhi, India.}, journal = {Science}, year = {2021}, month = {2021 Oct 14}, pages = {eabj9932}, abstract = {

Delhi, the national capital of India, has experienced multiple SARS-CoV-2 outbreaks in 2020 and reached population seropositivity of over 50\% by 2021. During April 2021, the city became overwhelmed by COVID-19 cases and fatalities, as a new variant B.1.617.2 (Delta) replaced B.1.1.7 (Alpha). A Bayesian model explains the growth advantage of Delta through a combination of increased transmissibility and reduced sensitivity to immune responses generated against earlier variants (median estimates; {\texttimes}1.5-fold, 20\% reduction). Seropositivity of an employee and family cohort increased from 42\% to 87.5\% between March and July 2021, with 27\% reinfections, as judged by increased antibody concentration after a previous decline. The likely high transmissibility and partial evasion of immunity by the Delta variant contributed to an overwhelming surge in Delhi.

}, issn = {1095-9203}, doi = {10.1126/science.abj9932}, author = {Dhar, Mahesh S and Marwal, Robin and Vs, Radhakrishnan and Ponnusamy, Kalaiarasan and Jolly, Bani and Bhoyar, Rahul C and Sardana, Viren and Naushin, Salwa and Rophina, Mercy and Mellan, Thomas A and Mishra, Swapnil and Whittaker, Charles and Fatihi, Saman and Datta, Meena and Singh, Priyanka and Sharma, Uma and Ujjainiya, Rajat and Bhatheja, Nitin and Divakar, Mohit Kumar and Singh, Manoj K and Imran, Mohamed and Senthivel, Vigneshwar and Maurya, Ranjeet and Jha, Neha and Mehta, Priyanka and A, Vivekanand and Sharma, Pooja and Vr, Arvinden and Chaudhary, Urmila and Soni, Namita and Thukral, Lipi and Flaxman, Seth and Bhatt, Samir and Pandey, Rajesh and Dash, Debasis and Faruq, Mohammed and Lall, Hemlata and Gogia, Hema and Madan, Preeti and Kulkarni, Sanket and Chauhan, Himanshu and Sengupta, Shantanu and Kabra, Sandhya and Gupta, Ravindra K and Singh, Sujeet K and Agrawal, Anurag and Rakshit, Partha and Nandicoori, Vinay and Tallapaka, Karthik Bharadwaj and Sowpati, Divya Tej and Thangaraj, K and Bashyam, Murali Dharan and Dalal, Ashwin and Sivasubbu, Sridhar and Scaria, Vinod and Parida, Ajay and Raghav, Sunil K and Prasad, Punit and Sarin, Apurva and Mayor, Satyajit and Ramakrishnan, Uma and Palakodeti, Dasaradhi and Seshasayee, Aswin Sai Narain and Bhat, Manoj and Shouche, Yogesh and Pillai, Ajay and Dikid, Tanzin and Das, Saumitra and Maitra, Arindam and Chinnaswamy, Sreedhar and Biswas, Nidhan Kumar and Desai, Anita Sudhir and Pattabiraman, Chitra and Manjunatha, M V and Mani, Reeta S and Arunachal Udupi, Gautam and Abraham, Priya and Atul, Potdar Varsha and Cherian, Sarah S} } @article {2376, title = {Proteome plasticity in response to persistent environmental change.}, journal = {Mol Cell}, volume = {81}, year = {2021}, month = {2021 08 19}, pages = {3294-3309.e12}, abstract = {

Temperature is a variable component of the environment, and all organisms must deal with or adapt to temperature change. Acute temperature change activates cellular stress responses, resulting in refolding or removal of damaged proteins. However, how organisms adapt to long-term temperature change remains largely unexplored. Here we report that budding yeast responds to long-term high temperature challenge by switching from chaperone induction to reduction of temperature-sensitive proteins and re-localizing a portion of its proteome. Surprisingly, we also find that many proteins adopt an alternative conformation. Using Fet3p as an example, we find that the temperature-dependent conformational difference is accompanied by distinct thermostability, subcellular localization, and, importantly, cellular functions. We postulate that, in addition to the known mechanisms of adaptation, conformational plasticity allows some polypeptides to acquire new biophysical properties and functions when environmental change endures.

}, keywords = {Acclimatization, Adaptation, Physiological, Animals, Environmental Exposure, Gene Expression Regulation, Fungal, Hot Temperature, Proteome, Saccharomycetales, Stress, Physiological, Transcriptome}, issn = {1097-4164}, doi = {10.1016/j.molcel.2021.06.028}, author = {Domnauer, Matthew and Zheng, Fan and Li, Liying and Zhang, Yanxiao and Chang, Catherine E and Unruh, Jay R and Conkright-Fincham, Juliana and McCroskey, Scott and Florens, Laurence and Zhang, Ying and Seidel, Christopher and Fong, Benjamin and Schilling, Birgit and Sharma, Rishi and Ramanathan, Arvind and Si, Kausik and Zhou, Chuankai} } @article {2290, title = {Strategies to target SARS-CoV-2 entry and infection using dual mechanisms of inhibition by acidification inhibitors.}, journal = {PLoS Pathog}, volume = {17}, year = {2021}, month = {2021 07}, pages = {e1009706}, abstract = {

Many viruses utilize the host endo-lysosomal network for infection. Tracing the endocytic itinerary of SARS-CoV-2 can provide insights into viral trafficking and aid in designing new therapeutic strategies. Here, we demonstrate that the receptor binding domain (RBD) of SARS-CoV-2 spike protein is internalized via the pH-dependent CLIC/GEEC (CG) endocytic pathway in human gastric-adenocarcinoma (AGS) cells expressing undetectable levels of ACE2. Ectopic expression of ACE2 (AGS-ACE2) results in RBD traffic via both CG and clathrin-mediated endocytosis. Endosomal acidification inhibitors like BafilomycinA1 and NH4Cl, which inhibit the CG pathway, reduce the uptake of RBD and impede Spike-pseudoviral infection in both AGS and AGS-ACE2 cells. The inhibition by BafilomycinA1 was found to be distinct from Chloroquine which neither affects RBD uptake nor alters endosomal pH, yet attenuates Spike-pseudovirus entry. By screening a subset of FDA-approved inhibitors for functionality similar to BafilomycinA1, we identified Niclosamide as a SARS-CoV-2 entry inhibitor. Further validation using a clinical isolate of SARS-CoV-2 in AGS-ACE2 and Vero cells confirmed its antiviral effect. We propose that Niclosamide, and other drugs which neutralize endosomal pH as well as inhibit the endocytic uptake, could provide broader applicability in subverting infection of viruses entering host cells via a pH-dependent endocytic pathway.

}, keywords = {Ammonium Chloride, Angiotensin-Converting Enzyme 2, Animals, Antiviral Agents, Cell Line, Chlorocebus aethiops, Chloroquine, Clathrin, COVID-19, Drug Synergism, Endocytosis, Endosomes, Humans, Hydrogen-Ion Concentration, Hydroxychloroquine, Macrolides, Niclosamide, Protein Binding, Protein Domains, SARS-CoV-2, Spike Glycoprotein, Coronavirus, Vero Cells, Virus Internalization}, issn = {1553-7374}, doi = {10.1371/journal.ppat.1009706}, author = {Prabhakara, Chaitra and Godbole, Rashmi and Sil, Parijat and Jahnavi, Sowmya and Gulzar, Shah-E-Jahan and van Zanten, Thomas S and Sheth, Dhruv and Subhash, Neeraja and Chandra, Anchal and Shivaraj, Akshatha and Panikulam, Patricia and U, Ibrahim and Nuthakki, Vijay Kumar and Puthiyapurayil, Theja Parassini and Ahmed, Riyaz and Najar, Ashaq Hussain and Lingamallu, Sai Manoz and Das, Snigdhadev and Mahajan, Bhagyashri and Vemula, Praveen and Bharate, Sandip B and Singh, Parvinder Pal and Vishwakarma, Ram and Guha, Arjun and Sundaramurthy, Varadharajan and Mayor, Satyajit} } @article {1595, title = {Prevention of pesticide-induced neuronal dysfunction and mortality with nucleophilic poly-Oxime topical gel.}, journal = {Sci Adv}, volume = {4}, year = {2018}, month = {2018 Oct}, pages = {eaau1780}, abstract = {

Organophosphate-based pesticides inhibit acetylcholinesterase (AChE), which plays a pivotal role in neuromuscular function. While spraying in the field, farmworkers get exposed to pesticides through the dermal route. Internalized pesticide inhibits AChE, which leads to neurotoxicity, cardiotoxicity, cognitive dysfunction, loss of endurance, and death in severe cases. Here, we present a nucleophilic pyridine-2-aldoxime-functionalized chitosan-based topical gel (-Oxime gel) that rapidly deactivates organophosphates, methyl parathion (MPT), on the skin of rats, which leads to reduced AChE inhibition in the blood and tissues. Testing the robustness of -Oxime gel, we report reduction in AChE inhibition following repeated dermal administration of MPT in the presence of -Oxime gel. Furthermore, -Oxime gel prevented MPT-induced neuromuscular dysfunction, loss of endurance, and locomotor coordination. We observe a 100\% survival in rats following topical MPT administration in the presence of -Oxime gel. This prophylactic gel may therefore help farmworkers by limiting pesticide-induced toxicity and mortality.

}, issn = {2375-2548}, doi = {10.1126/sciadv.aau1780}, author = {Thorat, Ketan and Pandey, Subhashini and Chandrashekharappa, Sandeep and Vavilthota, Nikitha and Hiwale, Ankita A and Shah, Purna and Sreekumar, Sneha and Upadhyay, Shubhangi and Phuntsok, Tenzin and Mahato, Manohar and Mudnakudu-Nagaraju, Kiran K and Sunnapu, Omprakash and Vemula, Praveen K} }