Biology subjects

Aravind, A.

Publications and source records attributed to Aravind, A..

3 recordsLinked to original sources

bioRxiv2026

Hailey-Hailey disease models identify synergistic therapeutic effects of MEK and ROCK inhibition

Hailey-Hailey disease (HHD) is a genetic skin blistering disorder lacking approved treatments despite linkage to ATP2C1 variants 25 years ago. Since knockout mice did not replicate HHD, we ablated ATP2C1 in human keratinocytes or chemically inhibited its encoded Golgi calcium pump SPCA1. In organotypic epidermis, SPCA1 deficiency or inhibition reproduced HHD pathology, disrupting desmosomal cadherins and severing cell-cell junctions, termed acantholysis. RNA sequencing of heterozygous cells identified dysregulation of actin and Rho GTPases along with EGF receptor signaling as potential pathogenic drivers. Accordingly, SPCA1-depleted organotypic epidermis and HHD biopsies exhibited cortical actin disorganization and hyper-phosphorylation of the Rho kinase (ROCK) target, myosin light chain. Rho activation was sufficient to induce acantholysis, while ROCK inhibition partially restored heterozygous keratinocyte cohesion. A fluorescent biosensor demonstrated ERK hyper-activation in heterozygous cells along with desmosomal cadherin mis-localization. Importantly, treating SPCA1-deficient keratinocyte sheets with MEK and ROCK inhibitors together fully restored their integrity. Our results show HHD blistering is driven by desmosome and cortical actin dysfunction that was mitigated by targeting MEK and ROCK with repurposed drugs, offering a viable treatment strategy. Moreover, our model provides a blueprint for replicating genetic epidermal disorders to delineate pathogenic mechanisms and vet therapeutics for other orphan skin diseases. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=199 SRC="FIGDIR/small/726679v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@b2de6aorg.highwire.dtl.DTLVardef@128411borg.highwire.dtl.DTLVardef@1ca760forg.highwire.dtl.DTLVardef@10cd6c7_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2026

Serial enrichment based quantitative proteomics enables deep and multiplexed profiling of post-translational modifications

Post-translational modifications (PTMs) play central roles in regulating protein function, localization, stability, and signaling networks. Comprehensive characterization of multiple PTMs, however, remains technically challenging due to limited sample availability, enrichment, incompatibilities, and analytical complexity. Here, we present an integrated serial enrichment workflow that enables quantitative profiling of multiple PTMs from a single biological sample. Using a streamlined strategy that combines StageTip-based fractionation with sequential immunoaffinity and metal oxide affinity enrichment, we achieved robust identification and quantification of lysine acetylation, lysine succinylation, phosphotyrosine, and global phosphorylation within the same sample. Application of this workflow resulted in deep proteome coverage alongside high-confidence PTM site identification with minimal sample loss and high reproducibility. Importantly, serial enrichment preserved PTM specificity and enabled comparative quantitative analysis across modification types. This approach provides a practical and scalable solution for integrated multi-PTM analysis, facilitating comprehensive interrogation of proteome regulation under limited sample conditions and offering broad applicability to systems biology, disease profiling, and translational proteomics studies.

systems biology↗

bioRxiv2021

Development of a Triazolobenzodiazepine-Based PET Probe for Subtype-Selective Vasopressin 1A Receptor Imaging

ObjectivesTo enable non-invasive real-time quantification of vasopressin 1A (V1A) receptors in peripheral organs, we sought to develop a suitable PET probe that would allow specific and selective V1A receptor imaging in vitro and in vivo. MethodsWe synthesized a high-affinity and -selectivity ligand, designated compound 17. The target structure was labeled with carbon-11 and tested for its utility as a V1A-targeted PET tracer by cell uptake studies, autoradiography, in vivo PET imaging and ex vivo biodistribution experiments. ResultsCompound 17 (PF-184563) and the respective precursor for radiolabeling were synthesized in an overall yield of 49% (over 7 steps) and 40% (over 8 steps), respectively. An inhibitory constant of 0.9 nM towards the V1A receptor was measured, while excellent selectivity over the related V1B, V2 and OT receptor (IC50 >10,000 nM) were obtained. Cell uptake studies revealed considerable V1A binding, which was significantly reduced in the presence of V1A antagonists. Conversely, there was no significant blockade in the presence of V1B and V2 antagonists. In vitro autoradiography and PET imaging studies in rodents indicated specific tracer binding mainly in the liver. Further, the pancreas, spleen and the heart exhibited specific binding of [11C]17 ([11C]PF-184563) by ex vivo biodistribution experiments. ConclusionWe have developed the first V1A-targeted PET ligand that is suitable for subtype-selective receptor imaging in peripheral organs including the liver, heart, pancreas and spleen. Our findings suggest that [11C]PF-184563 can be a valuable tool to study the role of V1A receptors in liver diseases, as well as in cardiovascular pathologies.

pharmacology and toxicology↗