摘要
Plant growth requires cell wall extension. The cotton AtRD22-Like I gene GhRDL1, predominately expressed in elongating fiber cells, encodes a BURP domain-containing protein. Here, we show that GhRDL1 is localized in cell wall and interacts with GhEXPA1, an α-expansin functioning in wall loosening. Transgenic cotton overexpressing GhRDL1 showed an increase in fiber length and seed mass, and an enlargement of endopleura cells of ovules. Expression of either GhRDL1 or GhEXPA1 alone in Arabidopsis led to a substantial increase in seed size; interestingly, their co-expression resulted in the increased number of siliques, the nearly doubled seed mass, and the enhanced biomass production. Cotton plants overexpressing GhRDL1 and GhEXPA1 proteins produced strikingly more fruits （bolls）, leading to up to 40% higher fiber yield per plant without adverse effects on fiber quality and vegetative growth. We demonstrate that engineering cell wall protein partners has a great potential in promoting plant growth and crop yield.
Plant growth requires cell wall extension. The cotton AtRD22-Like I gene GhRDL1, predominately expressed in elongating fiber cells, encodes a BURP domain-containing protein. Here, we show that GhRDL1 is localized in cell wall and interacts with GhEXPA1, an α-expansin functioning in wall loosening. Transgenic cotton overexpressing GhRDL1 showed an increase in fiber length and seed mass, and an enlargement of endopleura cells of ovules. Expression of either GhRDL1 or GhEXPA1 alone in Arabidopsis led to a substantial increase in seed size; interestingly, their co-expression resulted in the increased number of siliques, the nearly doubled seed mass, and the enhanced biomass production. Cotton plants overexpressing GhRDL1 and GhEXPA1 proteins produced strikingly more fruits （bolls）, leading to up to 40% higher fiber yield per plant without adverse effects on fiber quality and vegetative growth. We demonstrate that engineering cell wall protein partners has a great potential in promoting plant growth and crop yield.
基金
This research was supported by grants from the State Key Basic Research Program of China （2010CB126004）
the Chinese Academy of Sciences （KSCX2-EW-N-03）
the National Natural Science Foundation of China （31028003）, and the CAS/SAFEA International Partnership Program for Creative Research Teams.We thank Z. Jeff Chen and C.-H. Li for their helpful discussion. We thank T.-H. Zhang for his help on tractility assay. B.X., J.-Y.G., and X.-Y.C. designed the research
B.X., J.-Y.G., and B.Z. performed most of the experiments
X.-X.S., L.-J.W., and F.-G.L. did the cotton transformation and field trials
S.Y. and C.-Q.Y. compiled the literature data
B.X., X.-Y.C., and C.-J.L. wrote the manuscript. No conflict of interest declared.
