Functional Analysis Of ZmKHCP And ZmTYPA Genes Related To Embryogenic Callus Formation In Maize (Zea Mays L.)

Maize (Zea mays L.) is one of the world’s most important food crops, it has avariety of purposes such as food, industrial raw materials and feed. The status ofmaize is more and more important in people’s lives, and conventional breedingmethods for improve maize varieties have been far from meeting the demand for highquality maize. Plant trasgenetic technology provides new ways to maize geneticimprovement, it can take advantage of some good genes to enrich maize geneticresources. It is generally known that an ideal receptor system is the key of improvingtransgenic efficiency, and embryonic callus receptor system is a good choice.Therefore, further study the molecular mechanism of embryonic callus formation andexplore genes function related to embryonic callus, is important for establishing agood receptor system.ZmKHCP and ZmTypA are genes related to embryonic callus formation of maizeinbred line H99. This experiment based on pCAMBIA3301plasmid, constructed twoplant expression vectors pCAMBIA3301-35S: ZmKHCP-Term and pCAMBIA3301-35S: ZmTypA-Term. We transfered ZmKHCP and ZmTypA genes successfully toArabidopsis thaliana by Agrobacterium dip method, and obtained T2generationtransgenic plants. By inducing the transgenic callus of Arabidopsis thaliana, we foundthat transgenic plants of ZmKHCP occurs embryogenic callus after inducing20days,earlier than wild-type plants, indicating that ZmKHCP genes may promote callusformation. While transgenic plants of ZmTypA have no significant differencecompared with wild-type plants.Besides, we cloned ZmKHCP gene’s promoter successfully, constructed plantexpression vector PBI121-pZmKHCP and transferred it into Arabidopsis. Finally, weobtained transgenic plants. Through histochemical analysis of GUS activity, we found that GUS is expression in root, stem and leaf. At the same time, we successfullyconstructed3plant expression vectors of deleted promoter: pZmKHCP1185-3301,pZmKHCP705-3301and pZmKHCP354-3301, lay the foundation for further analyzethe core region of ZmKHCP gene promoter.We used statistical methods to observe phenotype differences betweenArabidopsis mutants and wild-type. Compared with wild-type plants, the resultsshowed that AtKHCP mutants have significant difference in plant height and leafwidth; while AtTypA mutants have significant difference in leaf length.