Characterization of the early fiber development gene, Ligon-lintless 1 (Li1), using microarray

Cotton fiber length is a key factor in determining fiber quality in the textile industry throughout the world. Understanding the molecular basis of fiber elongation would allow for improvement of fiber length. Ligon-lintless 1 (Li1) is a monogenic dominant mutation that results in short fibers. This mutant provides an excellent model system to study the molecular mechanisms of cotton fiber elongation. Microarray technology and quantitative real time PCR (qRT-PCR) were used to evaluate differentially expressed genes (DEGs) in the Ligon-lintless 1 (Li1) mutant compared to the wild-type. Although the results showed only a few differentially expressed genes at − 1, 3 and 7 days post anthesis (DPA); at 5 DPA, there were 1915 DEGs, including 984 up-regulated genes and 931 down-regulated genes. The critical stage for early termination of Li1 fiber elongation was 5 DPA, as there were the most differentially expressed genes in this sample. The transcription factors and other proteins identified might contribute to understanding the molecular basis of early fiber elongation. Gene ontology analysis identified some key GO terms that impact the regulation of fiber development during early elongation. These results provide some fundamental information about the TFs that might provide new insight into understanding the molecular mechanisms governing cotton fiber development.