The function of SAP30L (SAP30 like, ENSG00000164576) is as follows. [Isoform 1]: Functions as a transcription repressor, probably via its interaction with histone deacetylase complexes (PubMed:16820529, PubMed:18070604). Involved in the functional recruitment of the class 1 Sin3-histone deacetylase complex (HDAC) to the nucleolus (PubMed:16820529). Binds DNA, apparently without sequence-specificity, and bends bound double-stranded DNA (PubMed:19015240). Binds phosphoinositol phosphates (phosphoinositol 3- phosphate, phosphoinositol 4-phosphate and phosphoinositol 5-phosphate) via the same basic sequence motif that mediates DNA binding and nuclear import (PubMed:19015240, PubMed:26609676). {ECO:0000269|PubMed:16820529, ECO:0000269|PubMed:18070604, ECO:0000269|PubMed:19015240, ECO:0000269|PubMed:26609676}. [Isoform 2]: Functions as a transcription repressor; isoform 2 has lower transcription repressor activity than isoform 1 and isoform 3. . [Isoform 3]: Functions as a transcription repressor; its activity is marginally lower than that of isoform 1. .