NACA1, NACA2 and NACAP1 are members of the nascent polypeptide-associated complex (NAC) α subunit family that participate in preventing inappropriate targeting of non-secretory polypeptides to the endoplasmic reticulum (ER). As nascent polypeptide chains emerge from the ribosome, NACA proteins bind to these chains and block their interaction with the signal recognition particle (SRP), which normally targets nascent secretory peptides to the ER. Members of the α-NAC subunit family have sequence similarities with transcription-regulating proteins and are suggested to function as transcriptional coactivators potentiating c-Jun-mediated transcription. Most NACA proteins localize to both nucleus as well as cytoplasm, and contain NASLCA/B (NASLCα/β) and UBA (ubiquitin-associated) domains. The UBA domain is associated with proteins involved in the ubiquitin-proteasome pathway for protein degradation.
Function:
Cardiac- and muscle-specific transcription factor. May act to regulate the expression of genes involved in the development of myotubes. Plays a critical role in ventricular cardiomyocyte expansion and regulates postnatal skeletal muscle growth and regeneration. Involved in the organized assembly of thick and thin filaments of myofibril sarcomeres.
Subunit:
Interacts (via PXLXP motif) with the muscle-restricted histone methyltransferase SMYD1 (via MYND-type zinc finger).
Subcellular Location:
Cytoplasm. Nucleus.
Tissue Specificity:
Specifically expressed in heart and skeletal muscle: it is present in differentiated myotubes but not in myoblasts.
Post-translational modifications:
Phosphorylation of Ser-2015 by ILK during cell adhesion may promote nuclear localization. Phosphorylation of Thr-2131 by GSK3B may promote proteasome mediated degradation.
Similarity:
Contains 1 NASLCA/B (NASLCalpha/beta) domain.
Contains 1 UBA domain.
SWISS:
E9PAV3
Gene ID:
17938
Database links:
Entrez Gene: 17938 Human
|
|
