SPOC (Spen paralog and ortholog C-terminal) domain found in Arabidopsis thaliana flowering time control protein FPA and similar proteins
FPA plays a role in the regulation of flowering time in the autonomous flowering pathway by decreasing FLOWERING LOCUS C mRNA levels. It is required for RNA-mediated chromatin silencing of a range of loci in the genome. FPA cotranscriptionally recognizes aberrant RNA and marks it for silencing. It controls alternative cleavage and polyadenylation on pre-mRNAs and antisense RNAs. FPA functions redundantly with FCA to prevent the expression of distally polyadenylated antisense RNAs at the FLC locus. FPA belongs to the Spen (split end) protein family, whose members contain three N-terminal RNA recognition motifs (RRMs), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal SPOC domain. This model corresponds to the SPOC domain that is involved in developmental signaling and has also been proposed to be a phosphorylation binding module.
Jiyao W et al.(2023). "The conserved domain database in 2023.",