The roles of cell wall in pollen tube growth

【摘要】：正In flowering plants,male gametes are delivered into female gametophyte by pollen tube.Thus polar growth of pollen tube is essential for successful fertilization.Cell wall is one of the factors important for polar growth of pollen tube. To understand the roles of cell wall in pollen tube growth,we performed a large scale characterization of the genes that are involved in the biosynthesis of Arabidopsis pollen tube wall.The MGP2,MGP4,MGP8 and MGP9 genes encode different putative glycosyltransferases and involved in biosynthesis of cell wall pectic RG-11.The CSLD1 and CSLD4 encode cellulose synthase-like D proteins and may be involved in biosynthesis of cellulose.Mutations in MGP4 result in unstable pollen tube wall.The mpg2 single mutation and mpg8 mpg9 double mutation severely affected the growth pattern of pollen tubes.The csld1 csld4 double mutation caused a significant reduction of cellulose deposition in the pollen tube wall and a remarkable disorganization of the pollen tube wall layers,resulting in burst of pollen tube in in vitro culture. Conclusions:Our data indicate that the genes play important roles in pollen tube growth by involvement of biosynthesis of pollen tube wall to ensure the pattern formation and polar growth of pollen tube.