Correlation Between SNP And Expression Difference Of Black Hamster LRH-1 And Litter Size

In recent years, great harms to our production and life have came from the rodentsoutbreaking frequently in China. As the dominant farmland rodents of the northern plainsin China, Cricetulus barabens not only had a wide range of distribution and a strongreproductive ability, but also could harm agriculture and spread diseases. Therefore, it wasessential to clarify the mechanism of outbreaking in the rodents population, dynamiccharacteristics and high fertility and to take comprehensive actions to control agriculturerodents comprehensive in molecular biology level.Liver receptor homolog-1(LRH-1) was a transcription factor playing an importantphysiological role in early embryonic development and adult individuals. Also, LRH-1had an important control function in the embryos and gonadal development process andovulation process. In this paper, we chose Cricetulus barabensis as the experimentmaterials from Yinan and Qufu. The primers were designed according to the LRH-1geneof homologous species from GenBank, the475bp DNA,1870bp mRNA (variant1) and1956bp mRNA (variant2) of LRH-1gene were cloned using PCR technique, the sequencenumbers submitted to the GenBank respectively were JQ038149, JN367458andJN367459. LRH-1gene of Cricetulus barabensis includes eight exons and seven introns,which contained conservative GATA factor binding sites, E-box and typical TATA box inthe promoter. Two variants of LRH-1gene differed in the insert sequence of86bp, coded541and501amino acids respectively. The proportion of Leu, Trp were10.9%and11.2%,0.37%and0.4%respectively. Amounts of Alpha helix and Turn corner were included inthe secondary structure. The protein of variant2without zinc finger structure controled byER was an important form of LRH-1in breast cancer cells. The LRH-1mRNA sequencein Cricetulus barabensis was compared with the corresponding sequence of other19species embodied in GenBank. It showed high similarity in the level of both nucleotideacids (65.2%-88.6%) and amino acids (63.7%-90.6%). System evolution and clusteranalysis showed that LRH-1gene was relatively conservative in the evolution, thehomology of which was high in various species, as a candidate gene related to animalbreeding and bile acid synthesis process.SNP analysis of LRH-1gene5' control area about Cricetulus barabensis of differentfertility in Yinan and Qufu showed that the18SNPs were examined, including13transition sites and15transversion sites,16haplotypes were defined. The sequencenumbers submitted to the GenBank were JN585737-JN585752. DnaSP5.0calculationfound, in genetic diversity level Yinan population was higher than Qufu. Only one single haplotype in Qufu population indicated LRH-1gene was more conservative in Qufu. Inaddition, Fst, Nm and Dxy proved to exist the genetic differentiation of LRH-1genebetween the two Cricetulus barabensis populations in a low level. The result of Gstanalysis showed that80.8%genetic variation existed within populations. Correlationanalysis of foetuses showed that sequence varied in a low level in the individuals with3-5foetuses. Hd, ? and ?W increased gradually with the increasing numbers of foetuses.Numbers of foetuses, mutations and transitions had a very significant positivecorrelation(P?0.01). Upstream sequence of TATA box, mutations and exon1had asignificant positive correlation(P?0.05). There was no correlation among sequencebetween TATA box and exon1, mutations and transversions. That is to say, mutations andtransitions increased with the increasing numbers of foetuses and mutations were almostsituated in the upstream of the exon1and TATA box.The expression quantity of LRH-1gene in estrous Cricetulus barabensis showed thatLRH-1gene was expressed in heart, liver, spleen, stomach, lung, kidney, adrenal gland,ovary, uterus, testis, epididymis and brainand, liver was highest. Female gonad was higherthan male gonad, ovary was higher than kidney and adrenal gland. Also, ovary was100times of uterus. In sexual gland, the expression quantity of ovary was highest, then weremale adrenal gland, female adrenalgland, male kidney, female kidney, uterus, testis andepididymis. Expression quantity of LRH-1gene in the ovary declined gradually withincreasing foetuses, however, in the uterus decreased first and then increased. In differentgeographic populations, the male adrenal gland expression differences were mostsignificant and Yinan population was higher than Qufu in expression quantity. The resultrevealed that LRH-1might closely relate to ovulation, which was consistent with thefunction of LRH-1regulating ovarian development, embryonic development and synthesisof ovarian hormones. The study could help to reveal the relationship between LRH-1andreproduction, diseases of human. Moreover, the research provided new targets for earlydiagnosis and effective treatment of diseases.The study on LRH-1gene polymorphism of Cricetulus barabensis had an importantrole to knowing the relationship among polymorphism, expression quantity and foetuses.Meanwhile, the research laid the foundation for further study on physiological function ofLRH-1gene regulating complicated physiological activities in Cricetulus barabensis, thusproviding scientific basis for preventing rodents in the molecular genetics level.