Abstract
Cotton fiber is an ideal model to study cell elongation and cell wall construction in plants. During fiber development, some genes and proteins have been reported to be specifically or preferentially expressed. Mapping of them will reveal the genomic distribution of these genes, and will facilitate selection in cotton breeding. Based on previous reports, we designed 331 gene primers and 164 protein primers, and used single-strand conformation polymorphism (SSCP) to map and integrate them into our interspecific BC1 linkage map. This resulted in the mapping of 57 loci representing 51 genes or proteins on 22 chromosomes. For those three markers which were tightly linked with quantitative trait loci (QTLs), the QTL functions obtained in this study and gene functions reported in previous reports were consistent. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of 52 polymorphic functional primers showed that 21 gene primers and 17 protein primers had differential expression between Emian22 (Gossypium hirsutum) and 3–79 (G. barbadense). Both RT-PCR and quantitative real-time PCR (qRT-PCR) analyses of the three markers tightly linked with QTLs were consistent with QTL analysis and field experiments. Gene Ontology (GO) categorization revealed that almost all 51 mapped genes belonged to multiple categories that contribute to fiber development, indicating that fiber development is a complex process regulated by various genes. These 51 genes were all specifically or preferentially expressed during fiber cell elongation and secondary wall biosynthesis. Therefore, these functional gene-related markers would be beneficial for the genetic improvement of cotton fiber length and strength.
Highlights
Cotton fiber, the seed hair of cotton, is one of the longest single cells in higher plants, and originates from the epidermal cells in the ovular surface
Low polymorphism of functional markers To detect polymorphisms and to genotype the mapping population, single-strand conformation polymorphism (SSCP) was applied in this study primarily because it is inexpensive, easy to handle, does not require special devices, and was presumed to facilitate genome wide mapping of cotton [19,28]
We found that primer polymorphism of the functional markers (10.51%) was relatively low, which is consistent with the fact that markers derived from coding sequences have lower polymorphism because of their more highly conserved nature than non-coding sequences [29]
Summary
The seed hair of cotton, is one of the longest single cells in higher plants, and originates from the epidermal cells in the ovular surface. It is well known that fiber development is composed of four overlapping stages: fiber cell enlargement and initiation from 23 to 1 day post anthesis (DPA), fiber elongation after anthesis until 25 DPA, secondary cell wall cellulose deposition from 15 to 50 DPA, and fiber cell dehydration and maturation after 45 DPA [3]. This makes the cotton fiber a perfect experimental model to study the mechanism of plant cell elongation, wall development and cellulose biosynthesis [2,4]. Identification and analyses of genes preferentially expressed in the different stages will facilitate further understanding of fiber cell elongation and cellulose biosynthesis, and will result in improved cotton fiber quality and yield
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
