Effect Of Dys-1 Mutation On The Expression Of Neuromuscular Genes In Caenorhabditis Elegans And Verification

Caenorhabdits elegans is a common model organism whose genes have 40%homology with humans.The increased expression of dys-1 gene in the muscle of the nematode during spaceflight indicates that dys-1 gene may be an important factor in sensing gravitational changes in space.In order to reveal how dys-1 affects the neuromuscular gene expression of space-flight nematodes,I utilized DNA microarray to explore the effect of dys-1 mutation on the gene expression of nematodes under a space environment condition,and analyzed the effect of spaceflight on the expression changes of neuromuscular related genes in wild type(WT)and dys-1 mutant.I further performed simulated microgravity to verify the expression changes of partial genes detected in DNA microarray,and discuss which genes may be involved in microgravity-induced decline of nematode movement and whether these altered genes have gerneration hereditary.The analysis of GO function and KEGG signaling pathway for microarray data in spaceflight experiments showed that dys-1 mutation could influence gene expression profile under space environment.GO function and KEGG signaling pathway in dys-1 mutant were different from WT nematodes.Spaceflight and microgravity have fewer effects in dys-1 mutant than in WT worms.Mutation of dys-1 attenutated the expression alterations of neuromuscular related genes during spaceflight,and even resulted in reverse changes in dys-1 mutation compared with WT worms.The WT and dys-1 mutant were put on 3D cyclotron that was used to simulate microgravity for 16.5 days.qRT-PCR results showed that the alterations of six specific genes except nlp-22 affected by dys-1 mutation under simulated microgravity was similar with their changes in spaceflight condition.The expression alterations of flp-4,lev-11,hlh-1,cdh-3 and unc-27 were mainly affected by microgravity under space environment.Simulated microgravity significantly decreased locomotion ability in F0 generation of WT worms,but no change was observed in F1 generation.However,there were no significant changes in locomotion ability in both F0 and F1 generation of the dys-1 mutant.These results suggest that the nematode became insensitive to microgravity once dys-1 mutation.According to the change tendency of the gene expression,some genes might be related to the regulation of movement including unc-27,nlp-22,,flp-1,egl-5,flp-4,mgl-3 and unc-94.In this study,the expression levels of 16 neuromuscular related genes were examined in FO and F1 generation's nematodes.The results showed that most of genes were down-regulated in WT worms but up-regulated or unchanged in dys-1 mutant in two generations of nematodes.These findings suggest that the expression alterations of these genes have heredity after simulation microgravity.This study will provide a basis for the further study about how dys-1 gene participates in the regulation of nematode neuromuscular system in a space environment condition.