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Banasiak, K.

Publications and source records attributed to Banasiak, K..

2 recordsLinked to original sources

Pheromone-dependent olfaction bidirectionally regulates muscle extracellular vesicles formation

Extracellular vesicles (EVs) are involved in multiple biological processes; however, there is limited knowledge of the influence of environmental factors or other individuals in a population on EV-regulated systems. The largest evolutionarily conserved EVs, exophers, are a component of the C. elegans maternal somatic tissue resource management system induced by embryos developing in utero, and thus progeny of individuals with active exopher biogenesis (exophergenesis) appear to be privileged. Using this model, we investigated the inter-tissue and social regulatory mechanisms of exophergenesis. We found that the predominant male pheromone, ascr#10, increases exopher production in hermaphrodites via the G-protein-coupled receptor STR-173 in the ASK sensory neurons. In contrast, pheromones from other hermaphrodites in the population temper exophergenesis. Within the hermaphrodite, an increase in embryo accumulation drives pro-exopher signals, and the internal sensory neurons AQR, PQR, and URX play a central role in modulating exopher levels. This intricate process is regulated partly via the neuropeptides FLP-8 and FLP-21, which originate from the URX and AQR/PQR/URX neurons, respectively. Our results reveal a regulatory network integrating internal and external cues, including control of somatic EVs production by the nervous system in response to social signals.

physiology↗

Heterotypic Assembly Mechanism Regulates CHIP E3 Ligase Activity

The E3 ubiquitin ligases CHIP/CHN-1 and UFD-2 team up to accelerate ubiquitin chain formation. However, it remained largely unclear how the high processivity of this E3 set is achieved. Here we studied the molecular mechanism and function of the CHN-1/UFD-2 complex in Caenorhabditis elegans. Our data show that UFD-2 binding promotes the cooperation between CHN-1 and ubiquitin-conjugating E2 enzymes by stabilizing the CHN-1 U-box dimer. The HSP-1 chaperone outcompetes UFD-2 for CHN-1 binding and promotes the auto-inhibited CHN-1 state by acting on the conserved position of the U-box domain. The interaction with UFD-2 enables CHN-1 to efficiently ubiquitinate S-Adenosylhomocysteinase (AHCY-1), an enzyme crucial for lipid metabolism. Our results define the molecular mechanism underlying the synergistic cooperation of CHN-1 and UFD-2 in substrate ubiquitylation. HIGHLIGHTSO_LIE3 ligase UFD-2 stimulates ubiquitylation activity of CHIP/CHN-1 C_LIO_LIUFD-2 binding promotes dimerization of CHIP/CHN-1 U-box domains and utilization of E2 enzymes C_LIO_LIHSP70/HSP-1 by latching the U-box and TPR domains stabilizes the autoinhibitory state of CHIP/CHN-1, limiting interactions with E2s and UFD-2 C_LIO_LIAssembly with UFD-2 enables CHIP/CHN-1 to regulate lipid metabolism by ubiquitylation of S-Adenosylhomocysteinase C_LI

molecular biology↗