ribosome


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ribosome

 [ri´bo-sōm]
any of the intracellular ribonucleoprotein organelles concerned with protein synthesis, found either bound to cell membranes or free in the cytoplasm. They may occur singly or in clusters (polyribosomes). The genetic code is translated when ribosomes attach to messenger RNA.

ri·bo·some

(rī'bō-sōm),
A granule of ribonucleoprotein, 120-200 Ǻ in diameter, that is the site of protein synthesis from aminoacyl-tRNAs as directed by mRNAs.
Synonym(s): Palade granule

ribosome

/ri·bo·some/ (ri´bo-sōm) any of the intracellular ribonucleoprotein particles concerned with protein synthesis; they consist of reversibly dissociable units and are found either bound to cell membranes or free in the cytoplasm. They may occur singly or occur in clusters (polyribosomes).riboso´mal

ribosome

(rī′bə-sōm′)
n.
A structure composed of RNA and protein, present in large numbers in the cytoplasm of living cells and serving as the site for assembly of polypeptides encoded by messenger RNA.

ri′bo·so′mal (-sō′məl) adj.

ribosome

[rī′bəsōm]
Etymology: ribose + Gk, soma, body
an organelle composed of RNA and protein that functions in the synthesis of protein. Ribosomes interact with messenger RNA and transfer RNA to link amino acid into a polypeptide chain in a sequence determined by the sequence of nucleotides in the messenger RNA. Ribosomes may exist singly, in clusters as polysomes, or attached to the "rough" endoplasmic reticulum. See also translation.
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Ribosome

ri·bo·some

(rī'bŏ-sōm)
A granule of ribonucleoprotein, 120-150 Å in diameter, which is the site of protein synthesis from aminoacyl-tRNAs as directed by mRNAs.

ribosome

A spherical cell ORGANELLE made of RNA and protein which is the site of protein synthesis in the cell by linking amino acids into chains. Ribosomes may be free or may be attached to the endoplasmic reticulum. During translation, ribosomes attach to MESSENGER RNA molecules and travel along them, synthesizing polypeptides as they go.

ribosome

a small particle (not an ORGANELLE) found in the cytoplasm of all cells, composed of protein and RIBOSOMAL RNA. Each ribosome is composed of two subunits of different sizes which sediment at different rates during centrifugation (see ULTRACENTRIFUGE). PROKARYOTES have ribosome with 70 S size and mass; EUKARYOTES have larger ribosomes with 80 S size and mass. Ribosomes bind to the 5′ end of MESSENGER RNA (see POLYNUCLEOTIDE CHAIN) and travel towards the 3′ end, with TRANSLATION and POLYPEPTIDE synthesis occurring as they go along. Frequently several ribosomes are attached to one piece of mRNA, forming a POLYRIBOSOME.

Palade,

George Emil, Romanian-U.S. cell biologist and Nobel laureate, 1912–.
Palade granule - a granule of ribonucleoprotein, the site of protein synthesis from aminoacyl-tRNAs as directed by mRNAs. Synonym(s): ribosome
Weibel-Palade bodies - see under Weibel

ribosome

cell organelle; granule formed of ribonucleoprotein; site of protein synthesis, under influence of nuclear m-RNA

ribosome

ribonucleoprotein particles concerned with protein synthesis; they consist of two, one large and one small, reversibly dissociable units (called also 50S and 30S subunits) that are found either bound to cell membranes, particularly rough endoplasmic reticulum, or free in the cytoplasm. They may occur singly or in clusters, called polyribosomes or polysomes, which are ribosomes linked by mRNA and are actively engaged in protein synthesis.

ribosome binding site
a nucleotide sequence near the 5′ terminus of mRNA required for binding of mRNA to the small ribosomal subunit. Called also Shine-Dalgarno sequence.
References in periodicals archive ?
Aside from being highly mobile and delicate, the ribosome could deteriorate in three to four days in the laboratory, making its study very difficult, Yonath said.
This oak wood extract provides support for ribosomes, the tiny cellular factories responsible for accurately producing structural and functional proteins everywhere in the body.
VIO has been shown to bind both the 30S and 50S ribosome subunits and to inhibit ribosomal translocation by interference with the peptidyl tRNA acceptor site [13,14].
coli cells grown on normal medium showed the cell wall composed of outer and cytoplasm membranes enclosing a periplasmic space, the nucleoid containing fine DNA fibril and the cytoplasm containing numerous ribosomes.
Adjust the number of Ribosome stations to the number of groups in the class.
Looking more closely, the team found that instead of reading the stop sign as "stop," ribosomes interpreted the pseudouridine-containing codon as an instruction to insert one of the amino acids serine, threonine, phenylalanine or tyrosine into the protein.
As ribosomes are crucial to life, they are a major target for new antibiotics.
Our results show that the average ribosomal transit time, which represents the amount of time required for a ribosome to traverse an mRNA transcript, was 36.
STOCKHOLM: Three scientists who produced atom-by-atom maps of the mysterious, life-giving ribosome won the Nobel Prize for Chemistry on Wednesday, a breakthrough that has been vital for the development of new antibiotics.
Many known, commercially valuable antibiotics exert their effects by binding to the bacterial ribosome.
Leary is currently using this laboratory to study eukaryotic translation, the process by which messenger RNA is translated into proteins within the human 40S ribosome, to better understand how infectious diseases like hepatitis C and polio virus are transferred to humans.