Genetic Analysis And Clone Of Plant Regeneration Correlative Genes From Embryonic Callus In Maize (Zea Mays L.)

Regenerating to be a whole plant from callus is the final formalrepresentation for genetic transformation acceptors. As it's a quantitative trait controled by many genes, it is favorable to do the research on Quantitative Genetics as well as on gene expression level. Then the genetic information about the callus regeneration will be acquired and germs for transgenetic acceptors will be broadened.Twenty-one maize inbred lines commonly used in practice, such as 18599 (hong) and 18599(bai), were taken as experimental materials and six ones were screened as parents to build the six-parent diallel cross. Being cultured with immature embryo, all inbred lines and crosses were investigated on the number of regenerating plant. Researches were carried out on difference of the genotype, effect of combining ability (CA) , heredity pattern and heredity effect.Suppression subtractive hybridization (SSH) was used for 18599 (hong) for the first time to isolate embryonic callus regeneration correlative genes. Embryonic calli, multiplication cultured for three times, were transferred into regeneration medium.RNA were extracted from calli, which grew in the regeneration medium for 24, 48 and 72 hours respectively, and were equally mixed as Tester. RAN from correlative period calli before regeneration were mixed as Driver. After two subtractive hybridizations and two cycles of suppressive PCR, subtractive library was constructed. Reverse Northern Hybridization was used to screen out the differential expressed gene clones, which were designated as ZmECRG. EST were sequenced and submitted to NCBI database searching for homologous proteins. Known gene functions correlative to embryonic callus regeneration were analyzed. Several primers were designed for RT-PCR. Abundance and period of differential expressed genes correlative to embryonic callus regeneration were fished out.