Regulation of ribosome synthesis in Tetrahymena pyriformis. 1. Coordination of synthesis of ribosomal proteins and ribosomal RNA during nutritional shift-down

TY - JOUR

T1 - Regulation of ribosome synthesis in Tetrahymena pyriformis. 1. Coordination of synthesis of ribosomal proteins and ribosomal RNA during nutritional shift-down

AU - Dreisig, H

AU - Andreasen, P H

AU - Kristiansen, K

N1 - Keywords: Animals; Culture Media; Electrophoresis, Polyacrylamide Gel; Kinetics; Polyribosomes; RNA, Ribosomal; Ribosomal Proteins; Ribosomes; Tetrahymena pyriformis

PY - 1984

Y1 - 1984

N2 - When exponentially growing cells of Tetrahymena pyriformis are transferred to a non-nutrient medium the loss of whole cell RNA, 90% of which is ribosomal RNA, exhibits biphasic kinetics, whereas whole cell protein is lost at a constant rate. The ratio RNA/protein declines during the first 5 h of starvation and then remains constant during the subsequent period of starvation. The synthesis of the majority of the ribosomal proteins is coordinately regulated during a nutritional shift-down. Exponentially growing cells devote 17% of their capacity for protein synthesis to the production of ribosomal proteins. Upon starvation this proportion is rapidly reduced 3.5-fold. In long-time-starved cells the absolute rate of ribosomal protein synthesis is only about 4.5% of that of exponentially growing cells. The synthesis of ribosomal RNA and ribosomal proteins appears tightly coupled during the transition from growth to starvation. In long-time-starved cells the synthesis of ribosomal RNA and ribosomal proteins are stoichiometrically balanced with no significant degradation of de novo synthesized ribosomal proteins.

AB - When exponentially growing cells of Tetrahymena pyriformis are transferred to a non-nutrient medium the loss of whole cell RNA, 90% of which is ribosomal RNA, exhibits biphasic kinetics, whereas whole cell protein is lost at a constant rate. The ratio RNA/protein declines during the first 5 h of starvation and then remains constant during the subsequent period of starvation. The synthesis of the majority of the ribosomal proteins is coordinately regulated during a nutritional shift-down. Exponentially growing cells devote 17% of their capacity for protein synthesis to the production of ribosomal proteins. Upon starvation this proportion is rapidly reduced 3.5-fold. In long-time-starved cells the absolute rate of ribosomal protein synthesis is only about 4.5% of that of exponentially growing cells. The synthesis of ribosomal RNA and ribosomal proteins appears tightly coupled during the transition from growth to starvation. In long-time-starved cells the synthesis of ribosomal RNA and ribosomal proteins are stoichiometrically balanced with no significant degradation of de novo synthesized ribosomal proteins.

U2 - 10.1111/j.1432-1033.1984.tb08126.x

DO - 10.1111/j.1432-1033.1984.tb08126.x

M3 - Journal article

C2 - 6426953

SN - 1742-464X

VL - 140

SP - 469

EP - 475

JO - FEBS Journal

JF - FEBS Journal

IS - 3

ER -