InterPro domain: IPR035079

FLO and LFY proteins are floral meristem identity proteins [ 1 , 2 ]. Mutations in the sequences of these proteins affect flower and leaf development. LFY has been shown to bind semi-palindromic 19-bp DNA elements through its highly conserved C-terminal DNA-binding domain (DBD). In addition to its well-characterized DBD, LFY possesses a second conserved domain at its amino terminus (LFY-N). Crystallographic structure determination shows that LFY-N is a sterile alpha motif (SAM) domain that mediates LFY oligomerization. It allows LFY to bind to regions lacking high-affinity LFY-binding sites and to access closed chromatin regions. Experiments revealed that altering the capacity of LFY to oligomerize compromised floral function. It has been suggested that the biochemical properties of the SAM domain are evolutionary conserved in all plant species [ 3 ].

This entry represents a SAM domain found in various plant proteins which are homologues of floricaula (FLO) and Leafy (LFY).

1. LEAFY controls floral meristem identity in Arabidopsis. Cell 69, 843-59
2. UNIFOLIATA regulates leaf and flower morphogenesis in pea. Curr. Biol. 7, 581-7
3. A SAM oligomerization domain shapes the genomic binding landscape of the LEAFY transcription factor. Nat Commun 7, 11222