A suppressed gene in integument cells of a fiberless seed mutant in upland cotton |
| |
Authors: | Email author" target="_blank">Wang?Xue-deEmail author Jiang?Shu-li Li?Yue-you Xu?Ya-nong |
| |
Institution: | (1) College of Agriculture and Biotechnology, Zhejiang University, Zhejiang, 310029 Hangzhou, China |
| |
Abstract: | A fiberless seed mutant (fl) was identified in a commercial cotton (Gossypium hirsutum L.) variety Xu-Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of
the ovule, as was characterized by analysis of genes related to fiber differentiation and development. Two genes, fl-E6 and
FL-E6, were cloned from fl-integument cells and FL-fiber or integument cells, respectively. Compared with FL-E6, fl-E6 showed
a dramatic change in nucleotide sequence: (1) FL-E6 contained a tandem repetitive sequence in which GGCTCA (Gly-Ser) is repeated
five times between the 82nd and the 93rd codon from the first ATG codon, while in fl-E6 the same sequence is repeated four
times; (2) The fl-E6 gene encodes a polypeptide of 241 amino acids but lacks two codons between the 90th and 93rd codon and
three between the 171st and 174th relative to FL-E6; (3) There are also 12 nucleotide substitutions which would result in
7 amino acid differences between fl-E6 and FL-E6. Analysis of RT-PCR and Northerm Blot showed that expression of the fl-E6
gene is suppressed in the fl-integument cells, but highly expressed in FL-fiber cells. The difference between fl-E6 and FL-E6
may be associated with lower expression of fl-E6 in the fl-integument cells. Searches of protein databases with the FL-E6
gene sequence showed similarity to the protein backbones of two arabinogalactan-proteins (AGPs), one from the filtrate of
suspension-cultured cells ofPyrus cornmunis (AGPPc2) and the other fromNicotiana alata (AGPNa2). Although the function of the FL-E6 protein in differentiation and development of cotton fiber cells is not known,
the data indicate that the mutation of fl-E6 gene from FL-E6 gene may inhibit the fiber cell initiation from epidermal cells
of the outer integument of the ovule.
Project supported by the National Natural Science Foundation of China (Nos. 39770473 and 30170058), National Program of Plant
Gene Transfer (J00-B-002-10), National High Technology Research and Development (863) Program of China (No. 2001AA212081),
and Research Program of Ministry of Education of China (No. 0114) |
| |
Keywords: | Upland cotton Fiberless seed mutant Integument cells cDNA Arabinogalactan proteins |
本文献已被 万方数据 SpringerLink 等数据库收录! |
|