Overview
Oxygen is an essential molecule to most living things on Earth. Hemoglobin molecules function to assist in utilization of this molecule in different ways (Hardison, 1998). In plants, hemoglobins are used for intracellular transport of oxygen within the electron transport chain (Hardison, 1998). Bacteria Fungi and Protists also use these molecules intracellularly to transfer oxygen and other molecules in respiratory chain reactions (Hardison, 1998). In multicellular organisms like birds and mammals, hemoglobin is used for the transfer of oxygen from tissue to tissue via the blood stream. When blood is transported to the lungs, the hemoglobin molecules located in red blood cells bind oxygen molecules. From the lungs, these oxygenated red blood cells are transported to all the tissues of the body.
The human hemoglobin molecule is constructed of 2 types of subunits, the α and β-globin subnits. The human α-globin and β-globin subunit genes are located on two different chromosomes, 16 and 11 respectively (Protein-NCBI, 2011a; Protein-NCBI, 2011b). These two genes are said to have descended from a common ancestor approximately 450 million years ago from the jawed vertebrates (Hardison, 1998). For the purpose of this annotation, the human β-globin gene (HBB) and protein product will be explored. Topics such as gene location, gene and protein structure, mutations and disease will be explored. A phylogenetic analysis of the HBB gene will also be conducted to study homology between different groups of living organisms. NCBI Blast searches (Altschul et al., 1990), a multiple alignment too called ClustalW (Larkin et al., 2007) and the phylogenetic analysis tool, Phylip (U of W, Phylip, 2011) will be used to conduct this analysis. We hypothesize that Human Beta globulin will be well conserved throughout mammals, birds and amphibians; with mammals and amphibian being more closely related to birds, and most distant from each other. The furthest from Human Beta globulin will be the nematode, yeast, and bacterial genes.