COL4A2

from Wikipedia, the free encyclopedia
Type IV collagen, alpha 2
Type IV collagen, alpha 2
Ribbon model of the protein COL4A2 according to PDB  1LI1
other names
  • Alpha-2 type IV collagen
  • Collagen Alpha-2 (IV) chain
  • Type IV collagen alpha-2 chain
Properties of human protein
Mass / length primary structure 167,553 daltons / 1,712 amino acids
Identifier
Gene names COL4A2; I; PORES2
External IDs
Occurrence
Parent taxon Deuterostomia
Orthologue
human House mouse
Entrez 1284 12827
Ensemble ENSG00000134871 ENSMUSG00000031503
UniProt P08572 P08122
Refseq (mRNA) NM_001846 NM_009932
Refseq (protein) NP_001837.2 NP_034062.3
Gene locus Chr 13: 110.31 - 110.51 Mb Chr 8: 11.31 - 11.45 Mb
PubMed search 1284 12827

Type IV collagen, alpha 2 , also known as alpha-2 type IV collagen , is a network-forming collagen that is encoded by the COL4A2 gene in the human organism . Type IV collagen proteins are integral parts of the basement membrane , more precisely the lamina densa . It is for the most part expressed in amniocytes and in the gallbladder .

history

Griffin et al . found in 1987 in their studies with somatic cell hybrids and with the help of in situ hybridization that COL4A2 is located on the gene locus 13q34. The dispersion of other collagen genes helps prevent uneven crossing-over . Due to the fact that COL4A1 and COL4A2 have different properties, their local proximity to one another on the 13th chromosome helps to reduce the risk of a disruptive event. On the other hand, the local proximity of the two genes increases their coordinative regulation.

In 1995 Koizumi et al . Interspecific and subspecific mapping panels to locate COL4A2 in the centromeric region of chromosome 8 of a mouse.

function

Type IV collagens are associated with laminin , entactin and heparan sulfate - proteoglycans to form the basement membrane that separates the epithelium from the connective tissue . The C terminus , known as canstatin , is an inhibitor of angiogenesis and tumor growth. In addition, COL4A2 inhibits cell proliferation , cell migration of endothelial cells, the reduction of the membrane potential of mitochondria and induces apoptosis . More precisely, it induces Fas -dependent apoptosis and activates caspase -8 and -9 activity. Furthermore, COL4A2 acts as a ligand for α v β 3 - and α v β 5 - integrin .

Gene structure

COL4A1 and COL4A2 share a common bidirectional promoter and the adjacent 5 'regions of these two genes overlap. The COL4A2 gene has a silencer element within the 3rd intron on the 24 bp region . This element is able to inhibit the promoters of COL4A1 and COL4A2 , as well as the herpes simplex virus - thymidine promoter. The silencer element is specifically recognized as a core protein called SILBF .

Diseases

Mutations in the COL4A2 gene could cause the following diseases:

Individual evidence

  1. ↑ COL4A2. In: GeneCards (English).
  2. ^ GeneID 1284
  3. ↑ CA Griffin, BS Emanuel, JR Hansen, WK Cavenee, JC Myers: Human collagen genes encoding basement membrane alpha 1 (IV) and alpha 2 (IV) chains map to the distal long arm of chromosome 13 . (PDF) In: Proc Natl Acad Sci USA . 84, No. 2, January 1987, pp. 512-516. PMID 3025878 .
  4. ↑ T. Koizumi, E. Hendel, PA Lalley, M.-BN Tchetgen, JH Nadeau: Homologs of genes and anonymous loci on human chromosome 13 map to mouse chromosomes 8 and 14 . In: Mammalian Genome . 6, No. 4, April 1995, pp. 263-268. PMID 7613031 .
  5. ↑ UniProt P08572
  6. ↑ E. Poschl, R. Pollner, K. Kuhn: The genes for the alpha 1 (IV) and alpha 2 (IV) chains of human basement membrane collagen type IV are Arranged head-to-head and separated by a bidirectional promoter of unique structure . In: EMBO J . 7, No. 9, September 1988, pp. 2687-2695. PMID 2846280 .
  7. ^ R. Soininen, M. Huotari, SL Hostikka, DJ Prockop, K. Tryggvason: The structural genes for alpha 1 and alpha 2 chains of human type IV collagen are divergently encoded on opposite DNA strands and have an overlapping promoter region . (PDF) In: J Biol Chem . 263, No. 33, November 25, 1988, pp. 17217-17220. PMID 3182844 .
  8. ↑ A. Haniel, U. Welge-Lussen, K. Kuhn, E. Poschl: Identification and characterization of a novel transcriptional silencer in the human collagen type IV gene COL4A2 . (PDF) In: J Biol Chem . 270, No. 19, May 12, 1995, pp. 11209-11215. PMID 7744753 .
  9. ↑ COL4A2.  In: Online Mendelian Inheritance in Man . (English)
  10. ↑ Mutations in the COL4A2 gene. Orphanet, accessed July 12, 2016 .