Molecular Cloning CDNAs And Bioinformation Analysis Of Follicle-stimulating Hormone (FSH)-β Subunit And Luteinizing Hormone (LH)-β Subunit Of Schizothorax Prenanti

Gonadotrophins (GTH) is a kind of glycoprotein-hormone generated and secreted by vertebrate pituitary, whose function is to stimulate the development, differentiation and maturation of germ cells and maintain spermiation and ovulation. GTH I and II of Fish play the similar roles as follicle-stimulating hormone (FSH) and luteinizing hormone (LH) of mammal respectively. GTH consists of a andβsubunits and those two subunits combine to form dipolymer by noncovalent bond. The composition of a amino is the same while (3 amino is different, which functions specifically. Therefore, the investigation of the function ofβ-subunits of FSH and LH will assist in the reproduction of vertebrate and improve the reproductive performance of farm animals.Herein, we extracted total RNA from Schizothorax prenanti and designed the primer of (3-subunits of FSH and LH genes, and obtained the cDNA of that via rapid-amplification of cDNA ends (RACE) method.The result is described as below:(1) The total length of cDNA of P-subunit of FSH of Schizothorax prenanti is 624bp, and length of coding region is 393bp which codes 130 aminos whereas the total length of cDNA ofβ-subunit of LH is 640bp, the length of coding region is 441bp, which codes 146 aminos. Bioinformationally, the P-subunit of FSH is a negative charged protein equipped with 1 transbilayer helix and 3 hydrophobic regions, the molecular weight is 14.51kDa, the isoelectric point is 5.28, 12 phosphorylation sites are located on it. Theβ-subunit of LH is a negative charged protein equipped with 1 transbilayer helix and 4 hydrophobic regions, the molecular weight is 16.34kDa, the isoelectric point is 4.98,11 phosphorylation sites are located on it.(2)The homology analysis of the two coding genes of Schizothorax prenanti and other species including Mammals, Birds, Reptiles, Amphibian, Fishes showed:β-subunit of FSH has the highest homology as Cyprinus carpio (96.9%) and lowest homology as Bufo japonicus (37.6%), while theβ-subunit of LH has the most homology as cyprinus carpio (93.1%) and has the lowest homology as Homo (43.2%). The comparison of nucleotide homology showed that:β-subunit of FSH of Schizothorax prenanti has the highest homology as Cyprinus carpio (96.2%) and lowest homology as Japanese Quail (46.9%), while itsβ-subunit of LH has the highest homology as Cyprinus carpio (95.8%) and lowest homology as Japanese Quail (50.5%). The result can confirm that those two fragments obtained by clone are theβ-subunits of FSH and LH of Schizothorax prenanti, respectively. (3) The NJ and MP phylogenetic tree based on 22 kinds of vertebrate obtained by MAGA4.0 showed: Schizothorax prenanti belongs to Cypriniformes, which is in the cluster of cyprinus carpio, Ctenopharyngodon idellus and Mylopharyngodon piceus. This agrees with the conventional category. The result from similarity-comparison, genetic distance analysis and systematic arborization showed that the evolutionary rate ofβ-subunit of FSH is conservative whileβ-subunit of LH in amniota is faster that other vertebrates. This can reveal that the evolution of the two glycoproteins accords with the species evolution to function.