The Mechanism Of TMC Gene On Egg Laying Behavior In C.elegans

C.elegans has become an ideal model organism by researchers in nervous system and neural circuits,for its advantages of simple structure,strong reproductive ability,short growth cycle,simple nervous system,and its sequenced genome.Transmembrane channel-like gene(tmc),a well-known deaf gene,is a moly-transmembrane gene of unknown function.It is its moly-transmembrane structure which reveals TMC may act as a receptor,a transcripton,a channel or an iron pump.One of the controversial questions is whether TMC is a channel or not.We hope to reveal its function through our work to help deaf patients.Here we use dominant mutations of tmc-1(ok1859)and tmc-2(ok1302),both of which delete 2kb fragment,leading to loss of function of these genes.Compared with wild-type animals,TMC mutants maintain much more eggs and arrange a disorder of eggs in uterus.And through exogenous and endogenous addition of 5-HT,we found that tmc-1(ok1859)mutant,tmc-2(ok1302)mutant and double mutant worms all lay less eggs then wild-type worms.We suggest that there may be a partial loss of function in muscle of tmc-1 and tmc-2 mutations.To verify the experimental results,we overexpress cDNA of tmc-1 or/and tmc-2 mediated by different promoters,whose results also support our suggestion.In addition,electrophysiological and calcium imaging experiments have done,which show that TMCs may act as a background sodium channel,affecting excitability in muscles revolved in egg laying.Besides,we use NCA,a strong candidate as a background sodium channel,and TMC mutant to do behavioral experiments,which reveal that NCA and TMC are not on the same pathway.More addition,it is interesting to find that using tmc-1 or tmc-2 in mice can also rescue defection in egg laying behavior.Through our research,we find that TMC in C.elegans may act as a new background sodium channel.And the found can be somehow reached universally.