mRNA localization is a common mode of posttranscriptional regulation of gene expression that targets a protein to its site of function.
[
Proteins are highly dependent on cellular environments for stability and function, therefore, mRNA localization signals are crucial for maintaining protein function. The Gurken localisation signal is an RNA regulatory element conserved across many species of '']Drosophila
''Drosophila'' (), from Ancient Greek δρόσος (''drósos''), meaning "dew", and φίλος (''phílos''), meaning "loving", is a genus of fly, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or p ...
''. The element consists of an RNA stem loop within the coding region
The coding region of a gene, also known as the coding DNA sequence (CDS), is the portion of a gene's DNA or RNA that codes for a protein. Studying the length, composition, regulation, splicing, structures, and functions of coding regions compared ...
of the messenger RNA
In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of synthesizing a protein.
mRNA is created during the ...
that forms a signal for dynein
Dyneins are a family of cytoskeletal motor proteins (though they are actually protein complexes) that move along microtubules in cells. They convert the chemical energy stored in ATP to mechanical work. Dynein transports various cellular cargo ...
-mediated Gurken mRNA transport to the dorsoanterior cap near the nucleus
Nucleus (: nuclei) is a Latin word for the seed inside a fruit. It most often refers to:
*Atomic nucleus, the very dense central region of an atom
*Cell nucleus, a central organelle of a eukaryotic cell, containing most of the cell's DNA
Nucleu ...
of the oocyte
An oocyte (, oöcyte, or ovocyte) is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female ger ...
.
Mechanism of action
During ''Drosophila'' oogenesis, signaling between the germline
In biology and genetics, the germline is the population of a multicellular organism's cells that develop into germ cells. In other words, they are the cells that form gametes ( eggs and sperm), which can come together to form a zygote. They dif ...
and the soma
Soma may refer to:
Businesses and brands
* SOMA (architects), a New York–based firm of architects
* Soma (company), a company that designs eco-friendly water filtration systems
* SOMA Fabrications, a builder of bicycle frames and other bicycle ...
leads to the establishment of anterior-posterior polarity in the egg and the embryo. This process involves the interaction of gurken (grk), a TGFα-like protein, with torpedo (top), the ''Drosophila'' epidermal growth factor receptor
The epidermal growth factor receptor (EGFR; ErbB-1; HER1 in humans) is a transmembrane protein that is a receptor (biochemistry), receptor for members of the epidermal growth factor family (EGF family) of extracellular protein ligand (biochemistry ...
(EGFR).[ Localization of gurken RNA defines cell morphology by regulating the distribution of the gurken protein.][ Gurken mRNA transcripts which are not localized to the dorsal-anterior of an oocyte become silenced via post-translational modifications.]Polyadenylation
Polyadenylation is the addition of a poly(A) tail to an RNA transcript, typically a messenger RNA (mRNA). The poly(A) tail consists of multiple adenosine monophosphates; in other words, it is a stretch of RNA that has only adenine bases. In euka ...
of gurken transcripts occur throughout oogenesis; the length of the poly(A) tail determines the stage in oogenesis at which the gurken protein is adenylated.[ The gurken localization signal does not function properly if it is located in the 3' untranslated region.][
]
References
External links
*
Cis-regulatory RNA elements
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