Association of Plant p40 Protein with Ribosomes Is Enhanced When Polyribosomes Form during Periods of Active Tissue Growth

Abstract

Missouri 6521 1 (T.I.B.) p40s are acidic proteins of eukaryotic cells occurring either free in the cytoplasm or in association with ribosomes, the latter occurring in both monosomes and polysomes. p40s may play a role in the regulation of protein synthesis, although the exact mechanism is not known. Leaves of all 1 0 plant species examined here, including both monocots and dicots, contained proteins detected on immunoblots with Arabidopsis thaliana p40 antiserum. The number and apparent size of the protein bands were variable even among closely related species. Abundance of p40 relative to ribosomal content during soybean (Glycine max L.) seed germination and during seed and leaf development was examined. p40 abundance correlated with periods of active tissue growth and high polysome content. l h e plant growth regulator indole acetic acid caused an increase in polysome formation in etiolated pea (Pisum safivum L.) plants and a concomitant recruitment of p40 into polysomes. Subcellular localization at the microscopy leve1 indicated that the pattern of p40 staining is very similar to that for RNA, except that p40 is excluded from the nucleus. These data suggest that p40 is an accessory protein of the ribosome that might play a role in plant growth and development.A recently recognized class of acidic proteins that associate with ribosomes is called p40. These proteins are conserved among eukaryotes as distantly related as mammals (Makrides et al

Significant role for polysomes associated with the cytoskeleton in the control of protein synthesis during germination of triticale caryopses in the presence of abscisic acid

“…Abe et al (1995) found a 40-kD protein that may act to attach the ribosomes to the cytoskeleton. There is also a different protein, which is more abundant in actively translating -Hernandez et al, 1994-Hernandez et al, , 1996. The latest data presented by Davies et al (1998) indicate, that the role of the cytoskeleton would probably relate more to translational efficiency, than to segregation of mRNAs to different subpopulations of polysomes.…”

Environmental Performance Metrics for Daily Use in Synthetic Chemistry

“…p40s are acidic proteins of eukaryotic cells occurring either free in the cytoplasm or in association with ribosomes. p40s may play a role in the regulation of protein synthesis although the exact mechanism is not known 72.…”

Looking into laminin receptor: critical discussion regarding the non‐integrin 37/67‐kDalaminin receptor/RPSAprotein

“…The function of LAMR ribosomal incorporation is not known outside the observation that it is important for protein synthesis and ribosome biogenesis (Demianova et al, ; Scheiman et al, ; Venticinque et al, ), although it is alleged LAMR may not be a constitutive component (Malygin et al, ). While occurrence of ribosomal LAMR 37 may be enhanced in polysomes of actively growing cells (Garcia‐Hernandez et al, ) or by other stimuli (Fromm‐Dornieden et al, ), the protein is still found in free 40S subunits and present during initiation of translation (Ford et al, ; Valasek et al, ; Scheiman et al, ).…”