tRNATransfer RNA. Each tRNA attaches to a specific amino acid. As a protein is being assembled by a ribosome, the tRNA positions its associated amino acid in the proper sequential location specified by mRNA.
Transfer RNA, or tRNA, is a short RNA chain consisting of only 74-93 nucleotides that transfers specific amino acids to the polypeptide chain that is growing into RNA during translation. Each tRNA molecule can bind only one type of amino acid.
The structure of tRNA is usually described as a three-dimensional cloverleaf that, viewed from a certain angle, is L-shaped. This peculiar structure allows tRNA to fit neatly into the ribosome during the construction of RNA.
Each tRNA contains a specific anticodon triplet sequence that base-pairs to one or more codons to build an amino acid. Anticodons are made up of three nucleotides, just as codons are, and are critical in translation.
In a human, there are 497 nuclear genes that encode cytoplasmic rRNA, from which 324 tRNAs can be derived. Cytoplasmic tRNA genes are found on all but two human chromosomes (#22 and the Y chromosome). Other RNA genes are found in mitochondrial DNA. Recently, researchers have been very interested in how tRNA works; they have discovered at least one mitochondrial tRNA flaw that is linked to heart attack and low magnesium levels.
Web Resources On tRNA
Compilation of tRNA sequences and sequences of tRNA genes
Architecture & Structure of tRNA
Book Resources On tRNAtRNA: Structure, Biosynthesis, and Function by Dieter Soll and Uttam L. Rajbhandary
Aminoacyl-Trna Synthetases by Michael Ibba et. al.
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