{"id":1920,"date":"2024-03-03T17:01:37","date_gmt":"2024-03-03T17:01:37","guid":{"rendered":"https:\/\/cake.appscodestudio.com\/?p=1920"},"modified":"2024-03-03T17:01:39","modified_gmt":"2024-03-03T17:01:39","slug":"translation","status":"publish","type":"post","link":"https:\/\/cake.appscodestudio.com\/index.php\/2024\/03\/03\/translation\/","title":{"rendered":"Translation"},"content":{"rendered":"\n

The process of translation uses the information present in the\u00a0nucleotide\u00a0sequence of mRNA to direct the\u00a0synthesis\u00a0of a specific protein for use by the cell. Translation takes place on the ribosomes\u2014complex particles in the cell that contain RNA and protein. In prokaryotes the ribosomes are loaded onto the mRNA while transcription is still ongoing. Near the 5\u2032 end of the mRNA, a short sequence of nucleotides signals the starting point for translation. It contains a few nucleotides called a ribosome binding site, or Shine-Dalgarno sequence. In\u00a0E. coli<\/em>\u00a0the tetranucleotide GAGG is sufficient to serve as a binding site. This typically lies five to eight bases upstream of an initiation codon. The mRNA sequence is read three bases at a time from its 5\u2032 end toward its 3\u2032 end, and one\u00a0amino acid\u00a0is added to the growing chain from its respective aminoacyl\u00a0tRNA, until the complete protein chain is assembled. Translation stops when the ribosome encounters a termination codon, normally UAG, UAA, or UGA. Special release factors associate with the ribosome in response to these codons, and the newly synthesized protein, tRNAs, and mRNA all dissociate. The ribosome then becomes available to interact with another mRNA molecule.<\/p>\n\n\n\n

In eukaryotes the essence of protein synthesis is the same, although the ribosomes are more complicated. As with prokaryotic initiation, the signal sequence interacts with the 3\u2032 end of the small subunit\u00a0rRNA\u00a0during formation of the initiation complex.<\/p>\n\n\n\n

The issue of\u00a0fidelity\u00a0is important during protein synthesis, but it is not as crucial as fidelity during replication. One mRNA molecule can be translated repeatedly to give many copies of the protein. When an occasional protein is mistranslated, it usually does not fold properly and is then degraded by the cellular machinery. However, proofreading mechanisms exist within the ribosome to ensure accurate pairing between the codon in the mRNA and the anticodon in the tRNA.<\/p>\n\n\n\n

One of the crowning achievements of\u00a0molecular biology\u00a0was the elucidation during the 1960s of the\u00a0genetic code. Principals in this effort were\u00a0Har G. Khorana\u00a0and\u00a0Marshall W. Nirenberg, who shared a\u00a0Nobel Prize\u00a0in 1968. Khorana and Nirenberg used artificial\u00a0templates\u00a0and protein synthesizing systems in the test tube to determine the coding potential of all 64 possible triplet codons (see<\/em>\u00a0the\u00a0Click Here to see full-size table\"Thetable). The key feature of the genetic code is that the 20 amino acids are encoded by 61 codons. Thus, there is degeneracy in the code such that one amino acid is often specified by more than one codon. In the case of serine and leucine, six codons can be used for each. Among organisms that have been examined in detail, the code appears to be almost universal, from\u00a0bacteria\u00a0through\u00a0archaea\u00a0to eukaryotes. The known exceptions are found in the\u00a0mitochondria\u00a0of humans and many other organisms as well as in some species of bacteria. The structure within the genetic code whereby many amino acids are uniquely coded by the first two bases of the codon strongly suggests that the code has itself evolved from a more\u00a0primitive\u00a0code involving 16 dinucleotides. How the individual amino acids became associated with the different codons remains a matter of speculation.<\/p>\n","protected":false},"excerpt":{"rendered":"

The process of translation uses the information present in the\u00a0nucleotide\u00a0sequence of mRNA to direct the\u00a0synthesis\u00a0of a specific protein for use by the cell. Translation takes place on the ribosomes\u2014complex particles in the cell that contain RNA and protein. In prokaryotes the ribosomes are loaded onto the mRNA while transcription is still ongoing. Near the 5\u2032 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-1920","post","type-post","status-publish","format-standard","hentry","category-nucleic-acids"],"Cooking_time":"","jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/1920","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/comments?post=1920"}],"version-history":[{"count":1,"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/1920\/revisions"}],"predecessor-version":[{"id":1921,"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/1920\/revisions\/1921"}],"wp:attachment":[{"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/media?parent=1920"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/categories?post=1920"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cake.appscodestudio.com\/index.php\/wp-json\/wp\/v2\/tags?post=1920"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}