Oxysterol-binding protein(OSBP) and its homologues constitute a protein family in many eukaryotes, which is highly conservative, with a high-affinity receptor protein for oxysterols(oxygenated cholesterols), involving in cellular lipid metabolism, vesicle transport and signal transduction. A full-lenth c DNA sequence encoding ORP(Oxysterol binding proteinrelated proteins) was cloned with RT-PCR and rapid amplification of c DNA ends from the mulberry(Morus L.) variety M.multicaulis Perr. cv. Yu 71-1. The sequence was 1 974 bp and contained a 220 bp 5'-UTR and a 383 bp 3'-UTR, had an ORF of 1 371 bp encoding for 456 amino acids with predicted molecular weight of 51.97 k D and theoretical p I of 5.143. Online forecasting protein structural and functional sites and motif with PROSITE and Pfam showed that the protein was belonged to ORP family, having only ORD domain(OSBP-related ligand-binding domain) and containing the highly conserved fingerprint motif EQVSHHPP. Multiple sequence alignment showed that the protein was highly conserved. Phylogenetic tree analysis showed that the muberry had a closer genetic relationship with Fragaria vesca subsp. vesca L. and Prunus persica Batsch. var. duplex Rehd. Real-time PCR analysis showed that the expression level was higher in flower, young fruit, and ripe fruit than that in roots, stems and buds. Under salt stress, the expression of gene ORP increased first and then began to decline. It is indicated that the gene may be involved in some physiological responses to stress.

Objective: To construct a real-time fluorescence quantitative RT-PCR for the α-tubulin gene of Ca mellia sinensis.Methods: According to the α-tubulin gene sequence of C.sinensis available in GenBank,a pair of primers was designed and the amplified fragment of α-tubulin gene were linked with pTG19-T vector to construct recombined plasmid.Then the positive plasmid was diluted and the standard curve was established using SYBR GreenⅠ,and the melting curve was analyzed.Results: The linear range of standard curve Ct was from 14.56 to 27.09,and the correlation coefficient was 0.991.The melting curve showed a single peak with the temperature of 81±0.3℃.Conclusion: A real-time RT-PCR method for α-tubulin gene of C.sinensis was constructed successfully and it provided the basis for use of the α-tubulin gene of C.sinensis as a reference gene in quantitative analysis of differences in functional gene expression.