The Effect Of Reducing BCCIP Expression On Stress Resistance Of Caenorhabditis Elegans

The stress response is a non-specific response of the body to various stressors in the environment.The appropriate intensity of stressors can make the body produce "stress response" through nerve reflex,and then play a self-defense role.However,if the stress response is too strong or too long,it will cause "physical and mental diseases" on the body,which can lead to anxiety,tension,depression,weakened immunity,and even induce a variety of diseases.Therefore,the prevention of biological stress and treatment is paid more and more attention in recent years.Caenorhabditis elegans(C.elegans)is an excellent model organism with a short life cycle,small size,easy to operation,transparent body,easy observation and strong reproductive ability.The analysis of genome sequencing results confirmed that C.elegans is highly conserved in many evolutionary aspects and have 60%～80%homology with the human genome.Therefore,C.elegans has long become an important model organism in the research of developmental biology and molecular biology,especially in the study of stress response ability.BCCIP(BRCA2 and CDKN1 A interacting protein)is a protein that interacts with Breast Cancer Susceptibility Gene 2(BRCA2)and p21(Cyclin-Dependent Kinase Inhibitor 1 A,CDKN1A).Its low expression in various tumor tissues(including ovarian,renal and colorectal cancer)suggests its role in the development of tumors.In addition,it plays an important role in cell cycle,DNA damage repair and cytokinesis.However,so far,there have been no resports on the effects of BCCIP on stress response ability.It is known that BCCIP is highly conserved among different species,and have been identified from different species including Saccharomyces cerevisiae,C.elegans and Mus musculus.Gene sequence analysis that the BCCIP gene of C.elegans is homologous to the human BCCIP-β gene,and their tertiary structures are extremely similar.We speculated that the biological functions and mechanisms of them are similar.Therefore,studying the effect of BCCIP on the stress response ability of C.elegans well help us to speculate and understand the possible mechanism of BCCIP in human cells.In this paper,we selected C.elegans as the research object,by interfering with the transcription expression of BCCIP gene,to discuss the effects of BCCIP on different stress response abilities and the mechanism of BCCIP in stress response.First,in order to study the effect of BCCIP on the stress response ability of C.elegans,we constructed an RNA plasmid that can interfere the expression of BCCIP gene in C.elegans by using the L4440 gene interference vector.Gene-ds RNA was induced by IPTG and then introduced it into C.elegans by feeding method.Western Blot and RT-q PCR were used to analysed that the plasmid could effectively interfere the expression of BCCIP at the protein and m RNA levels respectively;Secondly,using the successfully constructed L4440-BCCIP plasmid to observe the effects of the loss of BCCIP expression on lifespan and egg production ability.The results showed that,knocking down the BCCIP gene have no effect on the lifespan of worms and total egg production,but the initial egg-laying time was delay,suggesting that BCCIP may play a role in the early development and maturation;Thirdly,in the stress response experiment,we found that BCCIP has different effects on the resistance of C.elegans to different stress stimuli.For example,low expression of BCCIP gene enhanced the resistance of heat stress,but reduced the resistance of ultraviolet radiation stress and oxidative stress;Fourth,the current research believes that DAF-16 transcription factor homologous to mammalian FOXO protein(related to the insulin signaling pathway),heat shock transcription factor HSF-1,and SKN-1 transcription factor homologous to mammalian Nrf2 protein are involved Nematode stress response regulation and key factor for life extension.In order to understand the mechanism of BCCIP on heat stress resistance,we investigated the effects of interference BCCIP expression on heat stress resistance signaling pathway in C.elegans.Further research found that,knockdown the BCCIP expression caused a significant increase in the expression of the DAF-16 and HSF-1 genes related to the heat stress resistance signaling pathway.At the same time,the expression levels of the downstream target genes hsp-12.6,hsp-70 and hsp-16.2 of the two transcription factors were also significantly increased,suggesting that the BCCIP affect the heat resistance of C.elegans might by inducing DAF-16 and HSF-1 signaling pathway.However,heat stress did not activate SKN-1.It is suggested that the three transcription factors have different emphasis on the regulation of different stresses.In summary,this paper uses the C.elegans model to study the effect of reducing BCCIP expression on the lifespan,reproduction,anti-stress and focuses on the mechanism of heat stress resistance.The experimental data provides a theoretical and experimental basis for further research on anti-stress,anti-aging and mechanism of action of BCCIP.