The Anaphase-Promoting Complex (APC) ubiquitin ligase affects chemosensory behavior inC. elegans

Abstract

The regulation of fundamental aspects of neurobiological function has been linked to the ubiquitin signaling system (USS), which regulates the degradation and activity of proteins and is catalyzed by E1, E2, and E3 enzymes. The Anaphase-Promoting Complex (APC) is a multi-subunit E3 ubiquitin ligase that controls diverse developmental and signaling processes in post-mitotic neurons; however, potential roles for the APC in sensory function have yet to be explored. In this study, we examined the effect of the APC ubiquitin ligase on chemosensation in Caenorhabditis elegans by testing chemotaxis to the volatile odorants, diacetyl, pyrazine, and isoamyl alcohol, to which wild-type worms are attracted. Animals with loss of function mutations in either of two alleles (g48 and ye143) of the gene encoding the APC subunit EMB-27 APC6 showed increased chemotaxis towards diacetyl and pyrazine, odorants sensed by AWA neurons, but exhibited normal chemotaxis to isoamyl alcohol, which is sensed by AWC neurons. The statistically significant increase in chemotaxis in the emb-27 APC6 mutants suggests that the APC inhibits AWA-mediated chemosensation in C. elegans. Increased chemotaxis to pyrazine was also seen with mutants lacking another essential APC subunit, MAT-2 APC1; however, mat-2 APC1 mutants exhibited wild type responses to diacetyl. The difference in responsiveness of these two APC subunit mutants may be due to differential strength of these hypomorphic alleles or may indicate the presence of functional sub-complexes of the APC at work in this process. These findings are the first evidence for APC-mediated regulation of chemosensation and lay the groundwork for further studies aimed at identifying the expression levels, function, and targets of the APC in specific sensory neurons. Because of the similarity between human and C. elegans nervous systems, the role of the APC in sensory neurons may also advance our understanding of human sensory function and disease.

The C. elegans neural editome reveals an ADAR target mRNA required for proper chemotaxis

“…The chemoattractant (odorant) was spotted on one side and an ethanol control on the other. Worms were placed in the middle and allowed to migrate for 1 hr prior to counting ( Wang et al, 2016 ) and the Chemotaxis Index of WT, adr-2(-) as well as WT + clec-41 and adr-2(-) + clec-41 to ( C ) Benzaldehdye (1:1000 dilution) or ( D ) Trimethylthiazole (1:10,000 dilution) was determined from 7 and 3 independent biological replicates, respectively. The chemotaxis index to trimethylthiazole (1:10,000 dilution) of worms expressing only the clec-41 3’ UTR in neural cells or expressing clec-41 in nonneural tissue was determined as a control ( Figure 5—figure supplement 1 ).…”

Genome-Wide Identification and Analysis of APC E3 Ubiquitin Ligase Genes Family in Triticum aestivum

“…Wheat plants were subjected to stress treatment when they reached the three-leaf stage. For the temperature stress treatment, the plants were placed in growth cabinets at different temperatures (8,15, and 25 • C) with a 16 h: 8 h, light: dark photoperiod, with the 8 • Ctreated wheat serving as the control. The wheat plants were inoculated with CWMV and Barley stripe mosaic (BSMV), as described previously [20].…”

“…APC is an E3-ubiquitin ligase that is conserved in eukaryotes. This enzyme is crucial for regulating cell proliferation and the cell cycle in eukaryotic cells, as it ubiquitinates specific target proteins for degradation by the 26S proteasome [ 8 , 9 , 10 ]. APC has been extensively studied in both fungal and animal cells because of its significant role in the cell cycle.…”