Isolation and Properties of Polyribosomes from Cerebral Cortex<sup>*</sup>

Campagnoni, Anthony T.; Mahler, Henry R.

doi:10.1021/bi00856a002

Cited by 77 publications

(11 citation statements)

References 14 publications

(32 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2). The kinetics of amino acid incorporation was similar to that observed by other workers who employed cell-free incorporation with rat brain fractions.3' 12 The present report shows that the loss in protein synthesis is, at least in part, the result of an inability of brain cell microsomes isolated from more mature neural tissue to participate in polypeptide synthesis (see Fig. 3).…”

supporting

confidence: 88%

“…This is similar to previous reports by others concerning cerebral polyribosomes isolated from more mature rat brain tissue. '0' 12 The exact nature of the alteration in brain microsomes that results in their inability to participate in protein synthesis is currently under study. Preliminary experiments in our laboratory have indicated that the alteration is not…”

mentioning

confidence: 99%

See 1 more Smart Citation

Alteration in Microsomal Protein Synthesis During Early Development of Mouse Brain

Johnson

Belytschko

1969

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Abstract.-The loss of protein synthesis during early mouse-brain development was shown to be the result, at least in part, of the inability of microsomes obtained from more mature neural tissue to participate in rapid polypeptide synthesis. The loss of brain microsomal activity was observed shortly after birth and continued until the animals were approximately ten days old. Despite the difference in synthetic activity, sucrose gradient profiles of microsomes and polyribosomes from young and more mature brain tissue were quite similar. The loss in protein synthesis was shown to be independent of available mRNA and not attributable to aminoacyl-RNA synthetases and tRNA binding activity.Introduction.-Several studies have indicated that the rates of macromolecular synthesis are altered during maturation of mammalian brain tissue. Higher rates of protein synthesis in younger brain tissue have been observed both in vivo and in vitro. 16 We have reported that both protein and RNA synthesis undergo a rapid decrement during early development of mouse brain tissue. The loss of protein synthesis during this critical period of development has been shown to be the results of a change in an intracellular component rather than an alteration in cellular membrane permeability.7 The present report involves an investigation of the identity of the intracellular component that is responsible, at least in part, for this altered rate of macromolecular synthesis. The role of microsomes and polyribosomes in this developmental phenomenon is described and compared to similar studies with brain and other mammalian tissues.

show abstract

supporting

confidence: 88%

mentioning

confidence: 99%

Alteration in Microsomal Protein Synthesis During Early Development of Mouse Brain

Johnson

Belytschko

1969

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…THE DEVELOPMENT of techniques for separating the free and membrane-bound ribosomes of cerebral tissue is essential not only for studying the functional specialization of these two ribosome populations but also for analyzing the compartmentalization of protein synthesis. At present the separation is achieved by exploiting either the difference in density or size between free ribosomes and rough microsomes (Z~M- ADAMS, 1967;CAMPAGNONI & MAHLER, 1967;MERITS et al, 1969;DUNN, 1970;ANDREWS & TATA, 1971;LERNER et al, 1971;MURTHY, 1972). The factors influencing these separations are only partially understood.…”

mentioning

confidence: 99%

QUANTITATIVE ISOLATION AND PROPERTIES OF NEARLY HOMOGENEOUS POPULATIONS OF UNDEGRADED FREE AND BOUND POLYSOMES FROM RAT BRAIN¹

Ramsey

Steele

1977

Journal of Neurochemistry

View full text Add to dashboard Cite

Abstract— A procedure is described for the preparation of free and bound polysomes from whole homogenate of rat brain tissue. Brain is homogenized in a sucrose‐polysome buffer medium high in KCl (250 mm). After a 12‐min centrifugation at 135,000 g, the free polysomes in the supernatant are decanted and saved, while the membrane bound polysomes in the pellet are resuspended in homogenizing medium, homogenized in the presence of detergent (Triton X‐100), centrifuged for 5min at 1470 g to remove nuclei, decanted, treated with deoxycholate and centrifuged for 10 min at 24,000 g to remove deoxycholate‐insoluble material. Polysomes in the two supernatants are harvested by centrifugation through sucrose gradients prepared in high KCl polysome buffer, and with or without cell sap. Free and bound polysomes prepared in this manner are undegraded, equally active in cell‐free protein synthesis, and largely free of the usual contaminants. Cross‐contamination is minimal (>10%). The recovery of polysomes is at least 95%. The distribution of ribosomes and polysomes in rat brain is 58% free and 42% membrane‐bound. The distribution of rat brain RNA is 65% ribosomal and 35% non‐ribosomal. Conditions are described for the visualization and analysis of the entire complement of free and bound ribosomes. The size fractionation procedure is rapid and reproducible, requires much less ultracentrifugation than the density‐gradient technique, and provides a nearly quantitative means of isolating undegraded free and bound polysomes of rat brain tissue.

show abstract

“…Using the Martin & Ames (1961) approximation, Williamson & Askonas (1967) calculated values of about 300S for the H-chain polyribosomes and 180-190S for the Lchain polyribosomes and estimated that they corresponded to polyribosomes of 12-18 and five or six ribosomes, respectively. These estimates do not appear completely consistent with the available data on the relationship between the number n of the ribosomes and the sedimentation coefficient .sn, Data for mammalian polyribosomes are only available up to about n = 10 and in this range appear to be in reasonable agreement (especially if they are referred to the same value for the monomer): within the limits of the experimental errors, most of them appear to fit the relationship se/si = na (Pfuderer, Cammarano, Holladay &Novelli, 1965), with cx = 0.58 (Gierer, 1963;Pfuderer et al 1965;Breillat & Dickman, 1966;Compagnoni & Mahler, 1967); for mouse plasmocytoma polyribosomes Kuff& Roberts (1967) gave oc = 0.62. With 8i = 80S, H-chain polyribosomes of 300S would have only nine or ten ribosomes, and L-chain polyribosomes four or five.…”

Section: Discussionmentioning

confidence: 86%

Electron microscopy of polyribosomes synthesizing immunoglobin chains. Comparison with sizes determined by density-gradient-sedimentation data

Petris¹

1970

Biochemical Journal

View full text Add to dashboard Cite

Polyribosomes from the immunoglobulin-producing plasma-cell tumour X5563 were fractionated on a linear sucrose gradient and fractions containing polyribosomes carrying heavy (H) and light (L) immunoglobulin chains were examined with the electron microscope. The size distribution of the polyribosomes in the various fractions was determined. The results are consistent with previous estimates by Williamson & Askonas (1967) of the size ofthe polyribosomes synthesizing immunoglobulin chains, despite some discrepancies in their calculations based on sedimentation data. In particular, polyribosomes of up to 18 ribosomes were present in the part of the gradient containing H-chain polyribosomes. The polyribosomal clusters appeared to betrue linear aggregates ofuniformly spaced ribosomes, arranged mostly in open or zig-zag configuration. The appearance of most of them does not seem to support a general helical model of the polyribosome.

show abstract

Isolation and Properties of Polyribosomes from Cerebral Cortex^*

Cited by 77 publications

References 14 publications

Alteration in Microsomal Protein Synthesis During Early Development of Mouse Brain

Alteration in Microsomal Protein Synthesis During Early Development of Mouse Brain

QUANTITATIVE ISOLATION AND PROPERTIES OF NEARLY HOMOGENEOUS POPULATIONS OF UNDEGRADED FREE AND BOUND POLYSOMES FROM RAT BRAIN¹

Electron microscopy of polyribosomes synthesizing immunoglobin chains. Comparison with sizes determined by density-gradient-sedimentation data

Contact Info

Product

Resources

About

Isolation and Properties of Polyribosomes from Cerebral Cortex*

Cited by 77 publications

References 14 publications

Alteration in Microsomal Protein Synthesis During Early Development of Mouse Brain

Alteration in Microsomal Protein Synthesis During Early Development of Mouse Brain

QUANTITATIVE ISOLATION AND PROPERTIES OF NEARLY HOMOGENEOUS POPULATIONS OF UNDEGRADED FREE AND BOUND POLYSOMES FROM RAT BRAIN1

Electron microscopy of polyribosomes synthesizing immunoglobin chains. Comparison with sizes determined by density-gradient-sedimentation data

Contact Info

Product

Resources

About

Isolation and Properties of Polyribosomes from Cerebral Cortex^*

QUANTITATIVE ISOLATION AND PROPERTIES OF NEARLY HOMOGENEOUS POPULATIONS OF UNDEGRADED FREE AND BOUND POLYSOMES FROM RAT BRAIN¹