Functional characterization of dhs-21 in C. elegans

Abstract

The L-xylulose dehydrogenase (XR) enzyme converts L-xylulose into xylitol. The enzyme orthologs catalyze the conversion in the L-arabinose and/or pentose phosphate pathway of various species from bacteria to mammals. However, the breakthrough of XR has not been well exploited and the pleiotropic roles of the XR have not been reported in animals. dhs-21 is the unique gene predictably encoding dicarbonyl/ L-xylulose reductase (DCXR) in the genome of Caenorhabditis elegans. I used C. elegans as a model organism to elucidate novel understandings: (1) It shows well-conserved functional domains of the mammalian XR and the activity of L-xylulose reduction; (2) It is expressed in the intestine, gonads, spermatheca valves and the uterus seam cell (utse) , oocytes and sperm. The expression of dhs-21 is directly regulated by DAF-16 and ELT-2; (3) The dhs-21 is necessary for longevity, reproduction and egg-laying retention. Along with enzymes R04B5.5, Y71F9B.9 and R08D7.7, I proved the existence of L-arabinose and gluconate pathways is required for reproduction; (4) It interacts with other genes, elt-2 and goa-1, for regulation of egg-laying.