Molecular cloning and expression analysis of GhLOF genes in upland cotton (Gossypium hirsutum L.).

Shoot branching, i.e., the timing and position of shoot growth, determines to a large extend the pattern of plant architecture, and is the result of the integration of a plant's genetic background and environmental cues. Many genes that are involved in the formation and outgrowth of axillary buds have been cloned, but the exact mechanism is still unclear. Branching pattern is an important agronomic trait in many crops, including cotton. In the present study, we cloned four genes from cotton, and designated them as GhLOF1/2/3/4. Sequence analysis revealed that all four genes shared conserved protein domains with LATERAL ORGAN FUSION (LOF) from Arabidopsis and TRIFOLIATE (Tf) from tomato. Phylogenetic analysis revealed that GhLOF3 and GhLOF4 were close to Tf because of their similar expression patterns, whereas GhLOF1 and GhLOF2 were differentially expressed.