Human transcription factor protein interaction networks

In participation of transcriptional regulation, transcription factors (TFs) interact with several other proteins. Here, we identified 7233 and 2176 protein-protein interactions for 110 different human TFs through proximity-dependent biotinylation (BioID) and affinity purification mass spectrometry (AP-MS), respectively. The BioID analysis resulted more high-confident interactions, highlighting the transient and dynamic nature of many of the TF interactions. Using clustering and correlation analyses, we identified subgroups of TFs associated with specific biological functions, such as RNA-splicing, actin signalling or chromatin remodeling. We also observed 203 TF-TF interactions, of which 175 were interactions with Nuclear Factor 1 (NFI) -family members, indicating uncharacterized cross-talk between NFI signalling and numerous other TF signalling. Moreover, TF interactions with basal transcription machinery were mainly observed through TFIID and SAGA complexes. This study, not only, provides a rich resource of human TF interactions, but also act as starting point directing future studies aimed at understanding TF mediated transcription.

Diverse Eukaryotic CGG-Binding Proteins Produced by Independent Domestications of hAT Transposons

The human transcription factor (TF) CGGBP1 (CGG-binding protein) is conserved only in amniotes and is believed to derive from the zf-BED and Hermes transposase DNA-binding domains (DBDs) of a hAT DNA transposon. Here, we show that sequence-specific DNA-binding proteins with this bipartite domain structure have resulted from dozens of independent hAT domestications in different eukaryotic lineages. CGGBPs display a wide range of sequence specificity, usually including preferences for CGG or CGC trinucleotides, whereas some bind AT-rich motifs. The CGGBPs are almost entirely nonsyntenic, and their protein sequences, DNA-binding motifs, and patterns of presence or absence in genomes are uncharacteristic of ancestry via speciation. At least eight CGGBPs in the coelacanth Latimeria chalumnae bind distinct motifs, and the expression of the corresponding genes varies considerably across tissues, suggesting tissue-restricted function.

Transcription factor 4 and its association with psychiatric disorders

The human transcription factor 4 gene (TCF4) encodes a helix–loop–helix transcription factor widely expressed throughout the body and during neural development. Mutations in TCF4 cause a devastating autism spectrum disorder known as Pitt–Hopkins syndrome, characterized by a range of aberrant phenotypes including severe intellectual disability, absence of speech, delayed cognitive and motor development, and dysmorphic features. Moreover, polymorphisms in TCF4 have been associated with schizophrenia and other psychiatric and neurological conditions. Details about how TCF4 genetic variants are linked to these diseases and the role of TCF4 during neural development are only now beginning to emerge. Here, we provide a comprehensive review of the functions of TCF4 and its protein products at both the cellular and organismic levels, as well as a description of pathophysiological mechanisms associated with this gene.