Dictionary » R » Ribosome

Ribosome

Definition

noun, plural: ribosomes

(Science: cell biology)

(1) A minute particle composed of protein and ribonucleic acid (RNA) that serves as the site of protein synthesis.

(2) A molecule consisting of two subunits that fit together and work as one to build proteins according to the genetic sequence held within the messenger RNA (mRNA). Using the mRNA as a template, the ribosome traverses each codon, pairing it with the appropriate amino acid. This is done through interacting with transfer RNA (tRNA) containing a complementary anticodon on one end and the appropriate amino acid on the other.

(3) A sphere-shaped structure found in the cytoplasm of prokaryotic and eukaryotic cells. Some ribosomes occur freely in the cytosol whereas others are attached to the nuclear membrane or to the endoplasmic reticulum (ER) giving the latter a rough appearance, hence, the name rough ER or rER.


Supplement

Ribosomes of prokaryotes (e.g. bacteria) are smaller than most of the ribosomes of eukaryotes (e.g. plants and animals). However, the plastids and mitochondria in eukaryotes have smaller ribosomes similar to those in prokaryotes – a possible indication of the evolutionary origin of these organelles.

In mid-1950s, ribosomes were first observed as dense particles or granules by George Palade with his electron microscope. In 1958, the term ribosome was proposed by the scientist, Richard B. Roberts.


Word origin: from ribonucleic acid and Greek: soma, meaning body.

Related forms: ribosomal (adjective).
Related terms: ribosome binding site, ribosome-lamella complex.


Please contribute to this project, if you have more information about this term feel free to edit this page



Results from our forum


What makes dominant allele dominant?

... to protein post-translational modifications. There can be mutation in the promotor changing significantly expression. If the binding of ribosome will be impaired, there will be much less of protein made. Single point mutations can lead to differences in binding of miRNAs. On the protein ...

See entire post
by JackBean
Thu Feb 27, 2014 5:20 pm
 
Forum: Genetics
Topic: What makes dominant allele dominant?
Replies: 5
Views: 1179

peptidyl transferase

Hey there. I have a little problem. :( PTC is an enzyme which catalyzes the peptide formation reaction. It is located in 60s subunit of ribosome. EC 2.3.2.12 . I actually need a pdb file of ptc for my docking issue. how can I find it??

See entire post
by Parisa
Tue Nov 05, 2013 10:11 pm
 
Forum: Cell Biology
Topic: peptidyl transferase
Replies: 2
Views: 737

peptidyl transferase center?!

Hey there. I have a little problem. :( PTC is an enzyme which catalyzes the peptide formation reaction. It is located in 60s subunit of ribosome. EC 2.3.2.12 . there are some pdb IDs like 3j3b n 3j3f but not for the pure protein. I actually need a pdb file of ptc for my docking issue. how ...

See entire post
by Parisa
Tue Nov 05, 2013 12:12 am
 
Forum: Bioinformatics
Topic: peptidyl transferase center?!
Replies: 1
Views: 483

Re: 'Evolution'-the most retarded myth ever.

... yet you are advocating a Jewish old earth creationist book by Lee Spetner? We see then that the mutation reduces the specificity of the ribosome protein and that means a loss of genetic information. ... Rather than saying the bacterium gained resistance to the antibiotic, it is more ...

See entire post
by Forests
Sun Oct 07, 2012 7:55 pm
 
Forum: Evolution
Topic: 'Evolution'-the most retarded myth ever.
Replies: 12
Views: 6416

Re: 'Evolution'-the most retarded myth ever.

... my goodness, they will have HELL to pay. http://en.wikipedia.org/wiki/Lee_Spetner We see then that the mutation reduces the specificity of the ribosome protein and that means a loss of genetic information. ... Rather than saying the bacterium gained resistance to the antibiotic, it is more ...

See entire post
by Cat
Sun Oct 07, 2012 3:35 pm
 
Forum: Evolution
Topic: 'Evolution'-the most retarded myth ever.
Replies: 12
Views: 6416
View all matching forum results

This page was last modified 11:01, 28 October 2008. This page has been accessed 300,751 times. 
What links here | Related changes | Permanent link