玉米自交系干旱应答基因的鉴定.pdfVIP

JournalofPlantPhysiologyandMolecularBiology 2007，33(6)：607—611 Identification of Drought-responsive Genes from Maize Inbred Lines LI Fu—Hua，FU Feng—Ling，SHA Li—Na，LI Wan—Chen Maize Research Institute~Key Laboratory of Ministry ofEducationfor Southwestern Crop Genetic Resources and Improvement,Sichuan Agricultural University,Ya’an，Sichuan 625014，China Abstract：To provide a useful piece of information for complexity ofthis trait．the variability in time and sever- the choice of molecular markers to be used in selection ity ofdrought，and the genotype by interactions with the of drought tolerance，mRNA differential display was used environment that affect the expression of candidate genes． to isolate genes from a drought-tolerant maize inbred line Drought tolerance is believed to be the result of coop— ‘8 1 565’．After drought stress，two down．regulated ex． erative interactions am ong multiple morphological，physi- pression gene fragments(MD 1 and MD2)and one up． ological and biochemical characters(Bray 1997)．Dif- regulated expression fragment(MD3)were obtained． ferent genotypes may have different responses to drought Results of sequence and homology analysis show that stress(Ludlow and Muchow 1990)．DNA molecular MD1 has 97％similarity with marK in maize chloroplast markers，especially expression sequence tag(EST)and genome，a gene encoding RNA maturase involved in single nucleotide polymorphism(SNP)developed from group II intron splicing ofRNA transcript；MD2 has 99％ intragenic expression sequence，are helpful for marker- similarity with the gene serine／threonine phosphory- assisted selection(MAS)to improve the drought toler- lase 2C in Sporobolus stapfianus；and MD3 has 99％ ance of maize varieties．These techniques heavily depend similarity with rice the gene encoding metacaspase，an on the identification and expression analysis of candi． arginine／lysine-speci