How did the globin gene evolve?

On the basis of this conserved basic structure and its prevalence in living organisms, it has been suggested that globin genes evolved from a common ancestral gene which, after successive duplications and speciation events, led to the genes that encode the widespread globin superfamily [1–5].

What is the structure of globin?

Globins are small globular metalloproteins consisting of about 150 amino acids. Typically, globins comprise eight α-helical segments (named A through H) that display a characteristical 3-over-3 α-helical sandwich structure.

What is the origin of hemoglobin?

Hemoglobins were originally discovered as abundant proteins in red blood cells of mammals and other jawed vertebrates (gnathostomes) that bind and release oxygen reversibly.

Where is globin produced?

The delta gene, which is located between the gamma and beta genes on chromosome 11 produces a small amount of delta globin in children and adults.

What are the globin genes?

The globins are a superfamily of heme-containing globular proteins, involved in binding and/or transporting oxygen. These proteins all incorporate the globin fold, a series of eight alpha helical segments. Two prominent members include myoglobin and hemoglobin.

What is the function of globin?

Globin proteins are ubiquitous in living organisms and carry out a variety of functions related to the ability of their prosthetic heme group to bind gaseous ligands such as O2, NO and CO. Moreover, they catalyze important reactions with nitrogen oxide species, such as NO dioxygenation and nitrite reduction.

How was hemoglobin discovered?

Hemoglobin (Hb) was accidentally discovered by Hünefeld in 1840 in samples of earthworm blood held under two glass slides. He occasionally found small plate-like crystals in desiccated swine or human blood samples [1, 2]. These crystals were later named as “Haemoglobin” by Hoppe-Seyler in 1864 [3].

How is globin produced?

Globin production is mainly controlled at the transcription level by a complex interaction of DNA sequences (cis-acting promoters, enhancers, and silencers) and soluble transcription factors (trans-acting factors) that bind to DNA or to one another to promote or suppress transcription.

How are the globin chain genes arranged?

Within each complex, the genes are all in the same 5′-3′ orientation, and are arranged in the order in which they are expressed during development. The α genes are duplicated in humans. Each α gene is approximately 4 kb long, interrupted by two small nonhomologous regions.

What is the function of globin Mcq?

Functions of globin It forms a protective hydrophobic pocket and prevents the conversion of ferrous form to ferric form and also permits reversible binding of oxygen with ferrous ion of heme.

Who discovered the structure of hemoglobin?

Max Perutz
In 1959, Max Perutz determined the molecular structure of hemoglobin by X-ray crystallography. This work resulted in his sharing with John Kendrew the 1962 Nobel Prize in Chemistry for their studies of the structures of globular proteins.

When was hemoglobin created?

The protein was discovered in 1840 by Friedrich Ludwig Hunefeld, a member of the German Biochemistry Association, according to “Lehninger Principles of Biochemistry” by David Nelson and Michael Cox. This discovery was made while viewing the blood of an earthworm.

How many types of globins are found in vertebrates?

Eight globins are known to occur in vertebrates: androglobin, cytoglobin, globin E, globin X, globin Y, hemoglobin, myoglobin and neuroglobin. Although the fold of the globin superfamily is highly evolutionarily conserved, the sequences that form the fold can have as low as 16\% sequence identity.

How evolutionarily conserved is the Globin superfamily fold?

Although the fold of the globin superfamily is highly evolutionarily conserved, the sequences that form the fold can have as low as 16\% sequence identity.

What are the members of the Globin superfamily?

Two prominent members include myoglobin and hemoglobin. Both of these proteins reversibly bind oxygen via a heme prosthetic group. They are widely distributed in many organisms. Globin superfamily members share a common three-dimensional fold.

What is the difference between flavohaemoglobins and globin E?

Flavohaemoglobins (FHb): chimeric, with an N-terminal globin domain and a C-terminal ferredoxin reductase-like NAD/FAD-binding domain. FHb provides protection against nitric oxide via its C-terminal domain, which transfers electrons to haem in the globin. Globin E: a globin responsible for storing and delivering oxygen to the retina in birds