[Cloning of pigeon invariant chain (Ii) gene by RACE].
In order to compare the structure and function of pigeon invariant chain (pIi) gene with other avian's, pIi gene was cloned using a method of RACE (Rapid Amplification of cDNA Ends). Firstly, according to high conservative nucleotide sequence of homologous fragment in avian invariant chain (Ii) gene, a pair of degenerated primer was designed, and a special DNA fragment was gained from pigeon spleen cell RNA by PCR. Then based on the sequence of gained DNA fragment, some new primers were designed, and the 3'terminal and the 5'terminal of pIi gene were cloned by RACE respectively. Finally a complete cDNA of pIi was to extend with newly designed primer by PCR. The product was identified by electrophresis and sequence analysis. The results of sequencing indicate that pIi gene is 1,050 bp in length (GenBank No. AY904337), which includes an open reading frame of 633 bp encoding a precursor protein with 211 amino acid residues. In comparison with the nucleotide sequences of other species' Ii genes, pIi is similar to chicken's, showing an overall identity of 82.8 with chicken and over 52.0 with human and other mammalian animals. In addition, some amino acid residues in Ii molecule manifest extremely conservative among animals, which suggests that they could have an important biological function.
Liu
Gang
G
Key Laboratory of Zoonoses of Anhui Province, Anhui Agricultural University, Hefei 230036, China.
Zhong
Da-Lian
DL
Liu
Xue-Lan
XL
Yu
Wei-Yi
WY
D000595:Amino Acid Sequence; D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D010856:Columbidae / Q000145:classification / Q000235:genetics*; D017931:DNA Primers; D005819:Genetic Markers / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques; D010802:Phylogeny; D016415:Sequence Alignment; D017385:Sequence Homology
D000944:Antigens, Differentiation, B-Lymphocyte; D017931:DNA Primers; D005819:Genetic Markers; D000949:Histocompatibility Antigens Class II; C045084:invariant chain