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HBE1
Hemoglobin subunit epsilon is a protein that in humans is encoded by the ''HBE1'' gene. Function The epsilon globin gene (HBE) is normally expressed in the embryonic yolk sac: two epsilon chains together with two zeta chains (an alpha-like globin) constitute the embryonic hemoglobin Hb Gower I; two epsilon chains together with two alpha chains form the embryonic Hb Gower II. Both of these embryonic hemoglobins are normally supplanted by fetal, and later, adult hemoglobin. The five beta-like globin genes are found within a 45 kb cluster on chromosome 11 in the following order: 5' - epsilon – gamma-G – gamma-A – delta – beta - 3'. See also *Hemoglobin * Human β-globin locus * Hemoglobin alpha chains (two genes, same sequence): ** ''HBA1'' ** ''HBA2 Hemoglobin, alpha 2 also known as ''HBA2'' is a gene that in humans codes for the alpha globin chain of hemoglobin. Function The human alpha globin gene cluster is located on chromosome 16 and spans about 30 kb, inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hb Gower I
The human embryonic haemoglobins were discovered in 1961. These include Hb-Gower 1, consisting of 2 zeta chains and 2 epsilon chains, and Hb-Gower 2, which consists of 2 αlpha-chains and 2 epsilon-chains, the zeta and epsilon chains being the embryonic haemoglobin chains. Embryonic hemoglobin is a tetramer produced in the blood islands in the embryonic yolk sac during the mesoblastic stage (from 3rd week of pregnancy until 3 months). The protein is commonly referred to as hemoglobin ε. Chromosomal abnormalities can lead to a delay in switching from embryonic hemoglobin. Hemoglobin Gower 1 Hemoglobin Gower 1 (also referred to as ζ2ε2 or Hb Gower-1) is a form of hemoglobin existing only during embryonic life, and is the primary embryonic hemoglobin. It is composed of two zeta chains and two epsilon chains, and is relatively unstable, breaking down easily. Hemoglobin Gower 2 Hemoglobin Gower 2 (also referred to as α2ε2 or Hb Gower-2) is a form of hemoglobin existing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HBG2
Hemoglobin subunit gamma-2 is a protein that in humans is encoded by the ''HBG2'' gene. Function The gamma globin genes (HBG1 and HBG2, this gene) 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) at birth. In some beta-thalassemias and related conditions, gamma chain production continues into adulthood. 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 Beta (, ; uppercase , lowercase , or cursive ; or ) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Ancient Greek, beta represented the voiced bilabial plosive . In Modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HBG1
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' - HBE1, epsilon – HBG2, gamma-G – gamma-A – HBD, delta � ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobin Subunit Zeta
Hemoglobin subunit zeta is a protein that in humans is encoded by the ''HBZ'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei .... Zeta-globin is an alpha-like hemoglobin. The zeta-globin polypeptide is synthesized in the yolk sac of the early embryo, while alpha-globin is produced throughout fetal and adult life. The zeta-globin gene is a member of the human alpha-globin gene cluster that includes five functional genes and two pseudogenes. The order of genes is: 5' - zeta - pseudozeta - mu - pseudoalpha-1 - alpha-2 - alpha-1 - theta1 - 3'. References Further reading * * * * * * * * * * * * * * * * * Hemoglobins {{gene-16-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobin
Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transportation of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the sole exception of the fish family Channichthyidae. Hemoglobin in the blood carries oxygen from the respiratory organs (lungs or gills) to the other tissues of the body, where it releases the oxygen to enable aerobic respiration which powers an animal's metabolism. A healthy human has 12to 20grams of hemoglobin in every 100mL of blood. Hemoglobin is a metalloprotein, a chromoprotein, and a globulin. In mammals, hemoglobin makes up about 96% of a red blood cell's dry matter, dry weight (excluding water), and around 35% of the total weight (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL of O2 per gram, which increases the total blood oxygen capacity seventy-fold compared to dissolved oxygen in blood plasma alone. The mammalian hemoglobin molecule can bind and transport up to four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human β-globin Locus
The human β-globin locus is a cluster of genes located on chromosome 11. It is responsible for creating the β-chains found in hemoglobin. This cluster consists of 5 genes: ϵ, Gγ, Aγ, δ, and β genes, that respective order downstream. These genes are controlled by a locus control region (LCR) and are differentially expressed throughout development. Expression of these genes is regulated in embryonic erythropoiesis by many transcription factors, including KLF1, which is associated with the upregulation of Hemoglobin A, adult hemoglobin in adult definitive erythrocytes, and KLF2, which is vital to the expression of embryonic hemoglobin. Mechanism The human beta globin (HBB) Locus (genetics), locus is located on the short arm of chromosome 11 in an AT-rich region and is part of the olfactory receptor (OR) gene superfamily. The locus is crucial to the production of the β-globin chain of hemoglobin A (HbA), which, alongside the α-globin chain derived from the Hemoglobin subunit a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HBA1
Hemoglobin subunit alpha, Hemoglobin, alpha 1, is a hemoglobin protein that in humans is encoded by the ''HBA1'' gene. Gene The human alpha globin gene cluster located on chromosome 16 spans about 30 kb and includes seven loci: 5'- zeta - pseudozeta - mu - pseudoalpha-1 - alpha-2 - alpha-1 - theta - 3'. The alpha-2 (HBA2) and alpha-1 (HBA1; this gene) coding sequences are identical. These genes differ slightly over the 5' untranslated regions and the introns, but they differ significantly over the 3' untranslated regions. Protein Two alpha chains plus two beta chains constitute HbA, which in normal adult life accounts for about 97% of the total hemoglobin; alpha chains combine with delta chains to constitute HbA-2, which with fetal hemoglobin (HbF), composed of alpha and gamma chains, make up the remaining 3% of adult hemoglobin. Clinical significance Alpha thalassemias result from deletions of each of the alpha genes as well as deletions of both HBA2 Hemoglobin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HBA2
Hemoglobin, alpha 2 also known as ''HBA2'' is a gene that in humans codes for the alpha globin chain of hemoglobin. Function The human alpha globin gene cluster is located on chromosome 16 and spans about 30 kb, including seven alpha like globin genes and pseudogenes: 5'- Hemoglobin subunit zeta, HBZ - HBZP1 - Mu hemoglobin, HBM - HBAP1 - HBA2 - HBA1 - HBQ1 -3'. The HBA2 (α2) and Hemoglobin, alpha 1, HBA1 (α1) coding sequences are identical. These genes differ slightly over the 5' untranslated regions and the introns, but they differ significantly over the 3' untranslated regions. Protein Two alpha chains plus two beta chains constitute Hemoglobin A, HbA, which in normal adult life accounts for about 97% of the total hemoglobin; alpha chains combine with delta chains to constitute Hemoglobin A2, HbA-2, which with Fetal hemoglobin, HbF (fetal hemoglobin), composed of alpha and gamma chains, make up the remaining 3% of adult hemoglobin. Clinical significance Alpha-thala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
