Gene-regulatory networks controlling inflorescence and flower development in Arabidopsis thaliana.

Reproductive development in plants is controlled by complex and intricate gene-regulatory networks of transcription factors. These networks integrate the information from endogenous, hormonal and environmental regulatory pathways. Many of the key players have been identified in Arabidopsis and other flowering plant species, and their interactions and molecular modes of action are being elucidated.

A single amino acid determines position specificity of an Arabidopsis thaliana CCoAOMT-like O-methyltransferase.

Caffeoyl-coenzyme A O-methyltransferase (CCoAOMT)-like proteins from plants display a conserved position specificity towards the meta-position of aromatic vicinal dihydroxy groups, consistent with the methylation pattern observed in vivo. A CCoAOMT-like enzyme identified from Arabidopsis thaliana encoded by the gene At4g26220 shows a strong preference for methylating the para position of flavanones and dihydroflavonols, whereas flavones and flavonols are methylated in the meta-position. Sequence alignments and homology modelling identified several unique amino acids compared to motifs of other CCoAOMT-like enzymes.