The Study of the Odorant Genes in the Land Mollusc
|Keywords||Odorant Odorant receptor Pseudogene Mollusca SMART cDNA library|
The olfaction is the process in which an animal perceives the volatile substances. Odorant, odorant binding protein and odorant receptor are essential in the initially process of the sensation. Odorant, usually volatiles with low molecular weight, binds odorant binding protein before complex with receptor, then arouses the electronic signal as in the process of vision. The olfaction is formed after the electronic signal is transferred to the CNS. The members of odorant receptor-coding genes form the largest gene family as known. The animal’s survival relies less on the olfactory and accordingly pseudogenization increases.I constructed a cDNA library of the domestic snail with Clontech SMART cDNA Library Construction Kit. With the total RNA extracted using the Invitrogen Trizol, first-strand cDNA synthesized, and with first-strand cDNA amplified with Long distance polymerase chain reaction (LD-PCR), the ds cDNA was digested by Sfi I and fractionated by CHROMA SPIN-400 column, before ligated toλTriplEx2 vector and packaged. Titering and blue/white tests showed the titter of the unamplified and the amplified were 1.22×106pfu/mL and 5.6×109 pfu/mL, respectively. The recombinant percentage reached 96.43%. From the cDNA Library constructed, I cloned randomly selected genes in which several were thought to be most homological with those confirmed or predicted olfactory genes. Their possible function was indicated by the well nesting in the evolutionary phylograms with olfactory genes terminals from plants, nematodes, insects, and some vertebrates.