Comparative Proteomic Analysis Of Calf Follicular Fluids And Adult Cattle

Juvenile in Vitro Embryo Production is of great significance to fully exploit the reproductive potential of excellent females, which not only can increase the rate of genetic gain, but also promote the commercialization of embryo production. However, the developmental capacity of calf oocytes in vitro is lower than that from adult cows. Follicular fluid is functioned as the micro-environment where oocytes grow and develop, so the proteins in the follicular fluid is closely related to the developmental potential of oocytes. In this study, the matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF MS) was used to analyse the different peptides of fresh follicle fluid between superovulation Chinese Holstein cattles and calves. Then two-dimensional electrophoresis was used to detect the different peoteins in two groups of follicular fluids. The utilization of two experiment methods could conduct a comprehensive analysis of follicular fluid proteomics. The objective of the experiment was to find out differentially peptide informations and expressed proteins related to the development of oocytes in follicular fluids of two groups, which will improve the theoretical basis for perfecting the culture system of calf oocytes. The results of research had been summarized as follows. l.In order to detect the different expression profile of the peptides in follicle fluid from superovulated Chinese Holstein cattle and calves, the matrix-assisted laser desorption ionization masss pectrometry was used to analysis the two groups of fresh follicle fluid. The models of peptides expression profile of two groups were successfully established, respectively. The results indicated that there were30-40peak signals in cattle group, and60-80peak signals in calves. By comparing the peak lists from the two different samples, we found that2specific peaks of1218.58(m/z) and1509.77(m/z) appeared in cattle group, similarly,1specific peak of953.54(m/z) in calf group. At last, we used MASCOT library to search the information of peptides, then gained some proteins related to these peptides information. Meanwhile, we found one kind of protein named fibrous protein Chain A, which was modified by The Crystal Structure. The results showed that15specific proteins existed in cattle group, and10specific proteins in calves. This is the first report to research peptides information in follicular fluid from superovulated calves by MALDI-TOF MS.2. The utilization of two-dimensional electrophoresis detected the different peoteins in two groups of follicular fluids. When350μg proteins were used in the24cm nonlinear IPG strip (pH4-7), about319spots in calf group and338spots in cattle group were respectively detected in2-DE maps using the Image Master2D platinum software. Four differentially expressed protein spots identified successfully by mass spectrometry, the results show that tumor necrosis factor alpha expressed in the adult cattle follicular fluid is less than calves significantly, and transferrin, oocyte maturation factor mos, BCL2L12expressed in the adult cattle follicular fluid is more than calves significantly.In conclusion, by MALDI-TOF MS comparing the two different samples, only one kind of protein named The Crystal Structure modified fibrous protein Chain A existed the two samples; by two-dimensional electrophoresis, four differentially expressed protein spots identified successfully by mass spectrometry, they are respectively transferrin, oocyte maturation factor mos, BCL2L12and tumor necrosis factor alpha.