Screening Of ABA Associated CDNA Clone And Preliminary Analysis Of The Function In Musa Acuminata

The banana fruit cDNA library was subdivided into 96-well plate and propagated. The well carrying target cDNA sequence was determined by PCR using a pair of specific oligonucleotide primers in the research.This method was faster.more simple and inexpensive than the filter isotope hybridization technique,furthermore,it did not need using isotope.Two cDNA sequences had been isolated by this method in the banana fruit cDNA library :the one was Mafral,the other was Maasrl.The result of BLASTn and BLASTx showed that Mafral's function was unknown,and might be a new gene.The result of conservative sequence analysis indicated that Mafral might contain a conservative domain of Exonuclease gene.The analyzing result of PROPSEARCH online made it known that Mafral might code a product which was highly homologous with Bone morphogenetic protein 7 precursor (BMP-7),Small/secreted glycoprotein precursor (SGP),and Capsid protein (F protein) (GPF).The analyzing result of OMIGA software made it clear that Mafral had an integrated open reading frame.The result of BLASTx showed that Maasrl might be homologous with Oryza sativa abscisic acid-inducible and stress-inducible protein (Asrl) mRNA (86%),Saccharum officinarum SoDip22 mRNA for drought inducible 22 kD protein ($4%)JLilium longiflorum anth (A23) mRNA (86%) , and Prunus armeniaca abscisic stress ripening protein homolog mRNA(82%). Maasrl included an integrated open reading frame by the analysis of GENSCAN_predicted online .Southern blot result showed that Maasrl had two copies in banana genome.Northern blot result indicated that the expression of Maasrl gradually ascended with time going on in harvested banana fruit.This change was consistent with the variational course of ethylene before climacteric period and fruit intenerating.The gene might associate with banana fruit ripening and might be an up-regulated gene in the fruit ripening and intenerating process.