Reduced tillering in Basmati rice T-DNA insertional mutant OsTEF1 associates with differential expression of stress related genes and transcription factors.

A T-DNA insertional mutant OsTEF1 of rice gives 60-80% reduced tillering, retarded growth of seminal roots, and sensitivity to salt stress compared to wild type Basmati 370. The insertion occurred in a gene encoding a transcription elongation factor homologous to yeast elf1, on chromosome 2 of rice. Detailed transcriptomic profiling of OsTEF1 revealed that mutation in the transcription elongation factor differentially regulates the expression of more than 100 genes with known function and finely regulates tillering process in rice by inducing the expression of cytochrome P450. Along with different transcription factors, several stress associated genes were also affected due to a single insertion. In silico analysis of the TEF1 protein showed high conservation among different organisms. This transcription elongation factor predicted to interact with other proteins that directly or indirectly positively regulate tillering in rice.