Host cell factor 1 (HCFC1, HCF1, or HCF-1), also known as VP16-accessory protein, is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

that in humans is encoded by the ''HCFC1''

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

Structure

HCF1 is a member of the highly conserved host cell factor family and encodes a protein with five Kelch repeats, a fibronectin-like motif, and six HCF repeats, each of which contains a highly specific cleavage signal. This nuclear

transcription coregulator In molecular biology and genetics, transcription coregulators are proteins that interact with transcription factors to either activate or repress the transcription of specific genes. Transcription coregulators that activate gene transcription are ...

is proteolytically cleaved at one or more of the six possible sites, resulting in the creation of an

N-terminal The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...

chain and the corresponding

C-terminal The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is ...

chain. The final form of this protein consists of noncovalently bound N- and C-terminal chains which interact through electrostatic forces.

Function

HCF1 is involved in control of the

cell cycle The cell cycle, or cell-division cycle, is the series of events that take place in a cell that cause it to divide into two daughter cells. These events include the duplication of its DNA (DNA replication) and some of its organelles, and subs ...

as well as having regulatory roles in a multitude of processes related to

transcription Transcription refers to the process of converting sounds (voice, music etc.) into letters or musical notes, or producing a copy of something in another medium, including: Genetics * Transcription (biology), the copying of DNA into RNA, the fir ...

. Additionally, work in model organisms point to HCF1 as being a putative

longevity The word " longevity" is sometimes used as a synonym for "life expectancy" in demography. However, the term ''longevity'' is sometimes meant to refer only to especially long-lived members of a population, whereas ''life expectancy'' is always d ...

determinant. Alternatively

spliced Spliced may refer to: *Spliced, the result of rope splicing Rope splicing in ropework is the forming of a semi-permanent joint between two ropes or two parts of the same rope by partly untwisting and then interweaving their strands. Splices ca ...

variants that encode different protein isoforms have been described; however, not all variants have been fully characterized. Mutations in this gene have been linked to disorders of the

cobalamine Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. It is one of eight B vitamins. It is required by animals, which use it as a cofactor in DNA synthesis, in both fatty acid and amino acid metabolism. It ...

metabolism.

Interactions

Host cell factor C1 has been shown to

interact Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...

with: *

BAP1 BRCA1 associated protein-1 (ubiquitin carboxy-terminal hydrolase) is a deubiquitinating enzyme that in humans is encoded by the ''BAP1'' gene. ''BAP1'' encodes an 80.4 kDa nuclear-localizing protein with a ubiquitin carboxy-terminal hydrolase (U ...

, *

CREB3 Cyclic AMP-responsive element-binding protein 3 is a protein that in humans is encoded by the ''CREB3'' gene. This gene encodes a transcription factor that is a member of the leucine zipper family of DNA binding proteins. This protein binds to th ...

, *

GABPA GA-binding protein alpha chain is a protein that in humans is encoded by the ''GABPA'' gene. Function This gene encodes one of three GA-binding protein transcription factor subunits which functions as a DNA-binding subunit. Since this subunit ...

, *

HDAC1 Histone deacetylase 1 (HDAC1) is an enzyme that in humans is encoded by the ''HDAC1'' gene. Function Histone acetylation and deacetylation, catalyzed by multisubunit complexes, play a key role in the regulation of eukaryotic gene expression. T ...

, *

HDAC2 Histone deacetylase 2 (HDAC2) is an enzyme that in humans is encoded by the ''HDAC2'' gene. It belongs to the histone deacetylase class of enzymes responsible for the removal of acetyl groups from lysine residues at the N-terminal region of the co ...

, * MLL, * OGT, *

PDCD2 Programmed cell death protein 2 is a protein that in humans is encoded by the ''PDCD2'' gene. Function This gene encodes a nuclear protein expressed in a variety of tissues. The rat homolog, Rp8, is transiently expressed in immature thymocytes ...

, *

POU2F1 POU domain, class 2, transcription factor 1 is a protein that in humans is encoded by the ''POU2F1'' gene. Interactions POU2F1 has been shown to interact with: * EPRS, * Glucocorticoid receptor, * Glyceraldehyde 3-phosphate dehydrogenase, ...

, *

PPP1CA Serine/threonine-protein phosphatase PP1-alpha catalytic subunit is an enzyme that in humans is encoded by the ''PPP1CA'' gene. Function The protein encoded by this gene is one of the three catalytic subunits of protein phosphatase 1 (PP1). PP ...

, *

SIN3A Paired amphipathic helix protein Sin3a is a protein that in humans is encoded by the ''SIN3A'' gene. Function The protein encoded by this gene is a transcriptional regulatory protein. It contains paired amphipathic helix (PAH) domains, which a ...

, * SP1, *

SUDS3 Sin3 histone deacetylase corepressor complex component SDS3 is an enzyme that in humans is encoded by the ''SUDS3'' gene. Function SDS3 is a subunit of the histone deacetylase (see HDAC1; MIM 601241)-dependent SIN3A (MIM 607776) corepressor com ...

, *

WDR5 WD repeat-containing protein 5 is a protein that in humans is encoded by the ''WDR5'' gene. This gene encodes a member of the WD repeat protein family. WD repeats are minimally conserved regions of approximately 40 amino acids typically bracketed ...

, and *

ZBTB17 Zinc finger and BTB domain-containing protein 17 is a protein that in humans is encoded by the ''ZBTB17'' gene. Interactions ZBTB17 has been shown to Protein-protein interaction, interact with TOPBP1, Host cell factor C1 and Myc. References ...

Structure

Function

Interactions

References

Further reading