| methuselah-like 5 | |
|---|---|
| Identifiers | |
| Organism | |
| Symbol | mthl5 |
| Alt. symbols | Gia |
| Entrez | 41438 |
| HomoloGene | 80839 |
| RefSeq (mRNA) | NM_141869.3 |
| RefSeq (Prot) | NP_650126.2 |
| UniProt | Q9VGG8 |
| Other data | |
| Chromosome | 3R: 11.88 - 11.89 Mb |
Methuselah-like 5 is a protein that in Drosophila is encoded by the Mthl5 (also known as Gia) gene.
Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific three-dimensional structure that determines its activity.
Drosophila is a genus of flies, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit. They should not be confused with the Tephritidae, a related family, which are also called fruit flies ; tephritids feed primarily on unripe or ripe fruit, with many species being regarded as destructive agricultural pests, especially the Mediterranean fruit fly. One species of Drosophila in particular, D. melanogaster, has been heavily used in research in genetics and is a common model organism in developmental biology. The terms "fruit fly" and "Drosophila" are often used synonymously with D. melanogaster in modern biological literature. The entire genus, however, contains more than 1,500 species and is very diverse in appearance, behavior, and breeding habitat.
In biology, a gene is a sequence of nucleotides in DNA or RNA that codes for a molecule that has a function. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic trait. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes as well as gene–environment interactions. Some genetic traits are instantly visible, such as eye color or number of limbs, and some are not, such as blood type, risk for specific diseases, or the thousands of basic biochemical processes that constitute life.
Methuselah-like 5 is a G protein coupled receptor (GPCR) that is essential for cardiac development in Drosophila. [1] Deletion of this gene interferes with cardioblast junction proteins, resulting in a broken hearted phenotype similar to other heterotrimeric cardiac G protein mutants. [1] Gia is expressed at stage 13 within bilateral rows of cardioblasts, but during stages 13–15 anterior cardioblasts demonstrate increasing expression while posterior cardioblast expression decreases. [1] By stage 16, Gia expression occurs only in aortic cardioblasts and is not present in the posterior segment cardioblasts. [1] Gia expression only occurs in the aorta and is presently the only gene known in Drosophila with a strictly aortic expression. [1] This gene is also known as Mthl5 (methuselah-like G protein coupled receptor) and is part of a gene family found in insects but not vertebrates. [2] Overexpression of Gia in a transgenic fly model did not cause any cardiac defects. [1]
Gap junctions are a specialized intercellular connection between a multitude of animal cell-types. They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells.
G-protein-coupled-receptors (GPCR) have a characteristic arrangement of seven transmembrane portions that culminate in an extracellular N-terminus and intracellular C-terminus. [3] More than 200 different GPCRs can be found in Drosophila . [3] GPCRs activation is facilitated by the g-proteins Gα, Gβ, and Gγ. [3] Drosophila have a relatively small number of G-proteins, making them a useful model for the study of GPCR outcomes. [3] Drosophila have a cardiac structure called the dorsal vessel that comprises a tubular structure with a cardioaortic valve and aortic-like outflow. [4] Genes important for cardiac development in Drosophila include NK2, MEF2, GATA, Tbx, and Hand. [4] [5]
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide referring to the free amine group (-NH2) located at the end of a polypeptide. Normally the amine group is bonded to another carboxylic group in a protein to make it a chain, but since the end of a protein has only 1 out of 2 areas chained, the free amine group is referred to the N-terminus. By convention, peptide sequences are written N-terminus to C-terminus, left to right in LTR languages. This correlates the translation direction to the text direction (because when a protein is translated from messenger RNA, it is created from N-terminus to C-terminus - amino acids are added to the carbonyl end).
The C-terminus is the end of an amino acid chain, terminated by a free carboxyl group (-COOH). When the protein is translated from messenger RNA, it is created from N-terminus to C-terminus. The convention for writing peptide sequences is to put the C-terminal end on the right and write the sequence from N- to C-terminus.
