Biomaterial Database

Changes in polypeptide initiation and elongation rates during the cell cycle of Chlamydomonas reinhardi. 1977

D M Baumgartel, and S H Howell

Changes in the rate of protein synthesis during the cell cycle of Chlamydomonas reinhardi have been measured by determining changes in the separate rates of polypeptide chain initiation and elongation and in the rate of incorporation of a radioactive amino acid. The rate of polypeptide chain elongation, determined from the relative rates of labeling of two size classes of polyribosomes, varies only about twofold during the cell cycle. The rate of polypeptide chain initiation, determined from an analysis of the distribution of ribosomes in monoribosomes (and ribosomal subunits) and polyribosomes, varies more than 25-fold. Also, the overall rate of protein synthesis during the cell cycle varies to the same extent as the rate of chain initiation. Measurement of protein synthetic rates using incorporation of a radioactive amino acid ([3H]arginine) underestimates the actual change in the rate of protein synthesis during the cell cycle. The vast changes in the initiation rate during the cell cycle suggest a mechanism for selecting specific messenger RNAs for translation at different cell-cycle stages.

UI	MeSH Term	Description	Entries
D010441	Peptide Chain Elongation, Translational	A process of GENETIC TRANSLATION, when an amino acid is transferred from its cognate TRANSFER RNA to the lengthening chain of PEPTIDES.	Chain Elongation, Peptide, Translational,Protein Biosynthesis Elongation,Protein Chain Elongation, Translational,Protein Translation Elongation,Translation Elongation, Genetic,Translation Elongation, Protein,Translational Elongation, Protein,Translational Peptide Chain Elongation,Biosynthesis Elongation, Protein,Elongation, Genetic Translation,Elongation, Protein Biosynthesis,Elongation, Protein Translation,Elongation, Protein Translational,Genetic Translation Elongation,Protein Translational Elongation
D010442	Peptide Chain Initiation, Translational	A process of GENETIC TRANSLATION whereby the formation of a peptide chain is started. It includes assembly of the RIBOSOME components, the MESSENGER RNA coding for the polypeptide to be made, INITIATOR TRNA, and PEPTIDE INITIATION FACTORS; and placement of the first amino acid in the peptide chain. The details and components of this process are unique for prokaryotic protein biosynthesis and eukaryotic protein biosynthesis.	Chain Initiation, Peptide, Translational,Protein Biosynthesis Initiation,Protein Chain Initiation, Translational,Protein Translation Initiation,Translation Initiation, Genetic,Translation Initiation, Protein,Translational Initiation, Protein,Translational Peptide Chain Initiation,Biosynthesis Initiation, Protein,Genetic Translation Initiation,Initiation, Genetic Translation,Initiation, Protein Biosynthesis,Initiation, Protein Translation,Initiation, Protein Translational,Protein Translational Initiation
D010940	Plant Proteins	Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which PLANT PROTEINS, DIETARY is available.	Plant Protein,Protein, Plant,Proteins, Plant
D011132	Polyribosomes	A multiribosomal structure representing a linear array of RIBOSOMES held together by messenger RNA; (RNA, MESSENGER); They represent the active complexes in cellular protein synthesis and are able to incorporate amino acids into polypeptides both in vivo and in vitro. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Polysomes,Polyribosome,Polysome
D002455	Cell Division	The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.	M Phase,Cell Division Phase,Cell Divisions,Division Phase, Cell,Division, Cell,Divisions, Cell,M Phases,Phase, Cell Division,Phase, M,Phases, M
D002696	Chlamydomonas	A genus GREEN ALGAE in the order VOLVOCIDA. It consists of solitary biflagellated organisms common in fresh water and damp soil.	Chlamydomona
D001120	Arginine	An essential amino acid that is physiologically active in the L-form.	Arginine Hydrochloride,Arginine, L-Isomer,DL-Arginine Acetate, Monohydrate,L-Arginine,Arginine, L Isomer,DL Arginine Acetate, Monohydrate,Hydrochloride, Arginine,L Arginine,L-Isomer Arginine,Monohydrate DL-Arginine Acetate
D012335	RNA, Ribosomal	The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)	Ribosomal RNA,15S RNA,RNA, 15S