Biology:HBG1

Generic protein structure example

Hemoglobin subunit gamma-1 is a protein that in humans is encoded by the HBG1 gene.

Function

The gamma globin genes (HBG1 and HBG2) are normally expressed in the fetal liver, spleen and bone marrow. Two gamma chains together with two alpha chains constitute fetal hemoglobin (HbF) which is normally replaced by adult hemoglobin (HbA) in the year following birth. In the non-pathological condition known as hereditary persistence of fetal hemoglobin (HPFH), gamma globin expression is continued into adulthood. Also, in cases of beta-thalassemia and related conditions, gamma chain production may be maintained, possibly as a mechanism to compensate for the mutated beta-globin. The two types of gamma chains differ at residue 136 where glycine is found in the G-gamma product (HBG2) and alanine is found in the A-gamma product (HBG1). The former is predominant at birth. The order of the genes in the beta-globin cluster is: 5' - epsilon – gamma-G – gamma-A – delta – beta - 3'.

Further reading

• "Gamma chain abnormalities and gamma-globin gene rearrangements in newborn babies of various populations.". Hemoglobin 15 (5): 349–79. 1992. doi:10.3109/03630269108998857. PMID 1802881. 
• "Sequences of G gamma, A gamma, and beta genes of the Greek (A gamma) HPFH mutant: evidence for a distal CCAAT box mutation in the A gamma gene.". Prog. Clin. Biol. Res. 191: 125–39. 1985. PMID 2413469. 
• "The multiple functions of hemoglobin.". Crit. Rev. Biochem. Mol. Biol. 30 (3): 165–96. 1995. doi:10.3109/10409239509085142. PMID 7555018. 
• "The human plasma proteome: history, character, and diagnostic prospects.". Mol. Cell. Proteomics 1 (11): 845–67. 2003. doi:10.1074/mcp.R200007-MCP200. PMID 12488461. 
• "beta 0 thalassemia, a nonsense mutation in man". Proc. Natl. Acad. Sci. U.S.A. 76 (6): 2886–9. 1979. doi:10.1073/pnas.76.6.2886. PMID 88735. Bibcode: 1979PNAS...76.2886C. 
• "Human T gamma globin chain is a variant of A gamma chain (A gamma Sardinia)". Proc. Natl. Acad. Sci. U.S.A. 76 (7): 3420–4. 1979. doi:10.1073/pnas.76.7.3420. PMID 291015. Bibcode: 1979PNAS...76.3420S. 
• "Sequence of the 3'-noncoding and adjacent coding regions of human gamma-globin mRNA". Nucleic Acids Res. 5 (12): 4625–30. 1979. PMID 318163. 
• "A new Hb variant: Hb F Sardinia gamma75(E19) isoleucine leads to threonine found in a family with Hb G Philadelphia, beta-chain deficiency and a Lepore-like haemoglobin indistinguishable from Hb A2". Acta Haematol. 53 (6): 347–55. 1975. doi:10.1159/000208204. PMID 808940. 
• "3' non-coding region sequences in eukaryotic messenger RNA". Nature 263 (5574): 211–4. 1976. doi:10.1038/263211a0. PMID 822353. Bibcode: 1976Natur.263..211P. 
• "Human beta-globin messenger RNA. I. Nucleotide sequences derived from complementary RNA". J. Biol. Chem. 252 (14): 5019–31. 1977. doi:10.1016/S0021-9258(17)40154-2. PMID 873928. 
• "Structure of human foetal deoxyhaemoglobin". J. Mol. Biol. 112 (1): 97–112. 1977. doi:10.1016/S0022-2836(77)80158-7. PMID 881729. 
• "Haemoglobin F Victoria Jubilee (alpha 2 A gamma 2 80 Asp-Try)". Biochim. Biophys. Acta 393 (1): 188–94. 1975. doi:10.1016/0005-2795(75)90230-5. PMID 1138921. 
• "Clinical course and molecular characterization of a compound heterozygote for sickle hemoglobin and hemoglobin Kenya". Am. J. Hematol. 41 (4): 289–91. 1993. doi:10.1002/ajh.2830410413. PMID 1283810. 
• "Reexamination of the African hominoid trichotomy with additional sequences from the primate beta-globin gene cluster". Mol. Phylogenet. Evol. 1 (2): 97–135. 1994. doi:10.1016/1055-7903(92)90024-B. PMID 1342932. 
• "Rapid identification by denaturing gradient gel electrophoresis of mutations in the gamma-globin gene promoters in non-deletion type HPFH". Br. J. Haematol. 80 (4): 533–8. 1992. doi:10.1111/j.1365-2141.1992.tb04569.x. PMID 1374633. 
• "A single point mutation is the cause of the Greek form of hereditary persistence of fetal haemoglobin". Nature 358 (6386): 499–502. 1992. doi:10.1038/358499a0. PMID 1379347. Bibcode: 1992Natur.358..499B. http://repub.eur.nl/pub/2476. 
• "Normal delta-globin gene sequences in Sardinian nondeletional delta beta-thalassemia". Hemoglobin 16 (6): 503–9. 1993. doi:10.3109/03630269208993118. PMID 1487421. 
• "A novel C-T transition within the distal CCAAT motif of the G gamma-globin gene in the Japanese HPFH: implication of factor binding in elevated fetal globin expression". Nucleic Acids Res. 18 (17): 5245–53. 1990. doi:10.1093/nar/18.17.5245. PMID 1698280. 
• "Hb F-Jiangsu, the first gamma chain variant with a valine----methionine substitution: alpha 2A gamma 2 134(H12)Val----Met". Hemoglobin 14 (2): 177–83. 1991. doi:10.3109/03630269009046959. PMID 1703137. 

External links

• Overview of all the structural information available in the PDB for UniProt: P69891 (Hemoglobin subunit gamma-1) at the PDBe-KB.