Identification of Differentially Expressed Genes in Axillary Tillers of Perennial Ryegrass

A PCR-based suppression subtractive hybridisation (SSH) technique was used to identify differentially expressed genes in the primary and axillary tillers of a perennial ryegrass (Lolium perenne L.) mutant with enhanced axillary tillering. A total of 310 expressed sequence tags (ESTs) were obtained representing 249 non-redundant sequences. The average EST sequence length was 249 nt and varied from 30 to 508 nt. Putative function was assigned to 152 ESTs by comparing sequences with publicly available databases of NCBI. The remaining 97 ESTs had no sequence similarity matches to any of the known databases. Several ESTs were selected as potential candidates for the control of axillary tiller formation. RUB1 conjugating enzyme and BIG protein were shown to play role in auxin response regulation, SHOOT1 protein was associated with fasciation mutation in soybean (Glycine max L.), and brassinosteroid LRR receptor kinase with brassinosteroid signalling.