Metabolism and Morphology of Ribonucleoprotein Particles From the Cell Nucleus of Lymphocytes

Frenster, John H.; Allfrey, Vincent G.; Mirsky, A. E.

doi:10.1073/pnas.46.4.432

Cited by 74 publications

(18 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The suspension was centrifuged at 1000 g for 10 minutes at 40 C. and the extraction was repeated on the sediment. This removes soluble proteins and nuclear ribosomes (Frenster, Allfrey and Mirsky, 1960). The pellet was suspended in 5 ml.…”

Section: Acidic Nuclear Proteinmentioning

confidence: 99%

Biochemical studies on human and rat breast tissues.

Smith¹,

King²,

Meggitt³

et al. 1966

Br J Cancer

View full text Add to dashboard Cite

Section: Acidic Nuclear Proteinmentioning

confidence: 99%

Biochemical studies on human and rat breast tissues.

Smith¹,

King²,

Meggitt³

et al. 1966

Br J Cancer

View full text Add to dashboard Cite

“…The specific activities of these proteins were quite different from those of total tumour protein so it seems unlikely that they represent simply cytoplasmic contamination. One possibly is that this fraction contains nuclear ribosomal protein (Frenster et al, 1960).…”

Section: Discussionmentioning

confidence: 99%

“…The supernatants were combined. This removes neutral-soluble proteins (globulins) and nuclear ribosomes (Frenster, Allfrey and Mirsky, 1960). …”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Nuclear Proteins and their Metabolism in Hormone Responsive and Unresponsive BR6 Mouse Mammary Tumours

Smith¹,

King²

1970

Br J Cancer

View full text Add to dashboard Cite

SUMMARY.-The histone, neutral and acidic nuclear-protein content of BR6 mouse mammary tumours have been measured and related to growth rate and hormone responsiveness. In unresponsive tumours, histone and neutral nuclear-protein content was inversely correlated with growth rate while acidic nuclear-proteins were directly correlated with growth rate. The histone content of these tumours was low when compared to pregnancy dependent tumours growing at the same rate under the same physiological conditions.In vitro incorporation of labelled amino acids into total protein and the nuclear proteins was also measured. Pregnancy independent tumours had higher rates of total protein synthesis than pregnancy dependent tumours. The rates of incorporation of amino acids into the nuclear proteins also tended to be higher in independent tumours.RECENT studies of hormone responsive and unresponsive tumours in a variety of species have indicated that the latter tend to be metabolically more active in that they have higher enzyme activities, co-factor concentrations, rates of glycolysis and respiration (King, 1968). In view of current speculation about the role of nuclear proteins in the control of metabolism (Bonner and Ts'o, 1964; Paul and Gilmour, 1968) differences in the nuclei of such tumours may be worth consideration. The amounts of basic (histone), acidic, and neutral nuclear proteins have therefore been measured in the nuclei of spontaneous, pregnancy dependent and independent mammary tumours in BR6 mice. The in vitro rates of incorporation of amino acids into these proteins, and into total protein, have also been estimated. The possible influence of growth rate on the results has been considered. MATERIALS AND METHODSTumours.-Spontaneous BR6 mouse mammary tumours were obtained from pregnant and non-pregnant mice. The characteristics of these tumours have been described previously (Foulds, 1949). Tumours which had appeared two or three times during successive pregnancies and had regressed to less than 50% of their maximum size within 5 days of parturition were considered pregnancy dependent. These were obtained from pregnant mice, 17-20 days after mating. Independent tumours were those known to grow in non-pregnant mice. Such tumours arise by a gradual or rapid loss of dependence on pregnancy for growth (Foulds, 1949). Pregnancy independent tumours were obtained from pregnant and non-pregnant mice.

show abstract

“…Dense particles have been previously demonstrated both in salivary gland chromosomes (17,18) and in nucleoli (19,20, and others). It now seems well established that these particles, similar in appearance to the particles in cytoplasm (21), are ribonucleoprotein in nature (22). They are also observable in many active genetic loci such as puffs and Balbiani rings of polytene chromosomes and loops of lampbrush chromosomes (cf.…”

Section: Figures 9 and 10mentioning

confidence: 98%

Electron Microscope Studies on Salivary Gland Cells

Jacob

Sirlin

1963

The Journal of Cell Biology

View full text Add to dashboard Cite

Salivary glands were fixed in cold 1 per cent osmium tetroxide in veronal-acetate buffer containing sucrose and embedded in methacrylate mixture or Araldite. The salivary gland nuclei of sclarids show a continuous production of nucleoli, which remain multiple and not consolidated into a single structure. The earliest recognizable nucleoli, which we call "elementary nucleoli," are aggregations of a few paired 40 A fibrils and a few 150 A particles, at many points within chromosome bands. Further development consists of the detachment of the elementary nucleoli from their points of origin and their subsequent mutual coalescence. As a result, dense patches of nucleolar material are formed which become large nucleoli at the surface of chromosomes, either attached to the band or free. The fully formed nucleoli have a characteristic dual structure with a narrow dense periphery and a broader less dense internum. Fibrils and particles are present in both regions, and the difference in density reflects differences in the packing of the two structural elements. The duality in structure is lost in later stages. The nucleolar fibrils appear to be similar to the chromosomal fibrils. The 150 A particles in nucleoli, chromosomes, and nuclear sap seem identical. The significance of these observations is discussed for nucleologenesis in general.

show abstract

Metabolism and Morphology of Ribonucleoprotein Particles From the Cell Nucleus of Lymphocytes

Cited by 74 publications

References 21 publications

Biochemical studies on human and rat breast tissues.

Biochemical studies on human and rat breast tissues.

Nuclear Proteins and their Metabolism in Hormone Responsive and Unresponsive BR6 Mouse Mammary Tumours

Electron Microscope Studies on Salivary Gland Cells

Contact Info

Product

Resources

About