scholarly journals PEPTIDASE INCREASE ACCOMPANYING GROWTH OF THE LARVAL SALIVARY GLAND OF DROSOPHILA MELANOGASTER

1949 ◽  
Vol 32 (5) ◽  
pp. 623-645 ◽  
Author(s):  
Elizabeth K. Patterson ◽  
Marjorie E. Dackerman ◽  
Jack Schultz
Keyword(s):  
Protein Synthesis ◽  
Drosophila Melanogaster ◽  
Salivary Gland ◽  
Cell Division ◽  
Total Nitrogen ◽  
Larval Growth ◽  
Growth Period ◽  
Growth Stages ◽  
Larval Salivary Gland ◽  
Coupled Reactions

1. The larval salivary gland of Drosophila melanogaster offers an opportunity to study growth in a tissue in which no cell division occurs but in which the cells increase in size. 2. Measurements of alanylglycine (AG)-peptidase content have been made in three stocks of Drosophila melanogaster at different growth stages of the larval salivary gland, and have been correlated with its total nitrogen and volume. 3. During the prepupal instar, the AG-peptidase content of the gland increases parallel with total nitrogen but decreases when histolysis of the gland begins. Conversely, a benzoyl-l-arginineamide-hydrolyzing endopeptidase is not measurable until histolysis sets in. 4. In the final larval growth period of a giant mutant, there is a concomitant increase in peptidase, total nitrogen, and volume of the gland. 5. A similar association of peptidase content and total nitrogen is found in comparing glands of different sizes from the giant stock, at the time of maximal peptidase content in the prepupa. 6. The data are interpreted as evidence for an association of AG-peptidase with growth of the cells in the gland. This agrees with the earlier interpretation by Linderstrøm-Lang and Holter of data obtained from study of more complex tissues. 7. A survey of the available measurements of peptidase content in other organisms shows that wherever an increase of cell substance occurs, peptidase content increases. Conversely, peptidase remains constant where cell division is unaccompanied by an increase of cell substances. 8. The joint association of peptidases and pentosenucleic acids with protein synthesis is pointed out. 9. The possiblity is considered that peptidases may be essential parts of a unit in which coupled reactions necessary for protein synthesis occur. The rôle of the peptidases in this system is discussed. They may act either synthetically to form new peptide linkages (problematic), or hydrolytically to mobilize the necessary specific amino acids.

p75, a polypeptide component of karyoskeletal protein-enriched fractions associated with transcriptionally active loci of Drosophila melanogaster polytene chromosomes

1988 ◽  
Vol 8 (5) ◽  
pp. 1877-1886
Author(s):  
B M Benton ◽  
S Berrios ◽  
P A Fisher
Keyword(s):  
Tissue Culture ◽  
Drosophila Melanogaster ◽  
Transcriptional Regulation ◽  
Salivary Gland ◽  
Indirect Immunofluorescence ◽  
Polytene Chromosomes ◽  
Nuclear Interior ◽  
Culture Cells ◽  
Tissue Culture Cells ◽  
Larval Salivary Gland

A 75-kilodalton polypeptide has been identified which copurifies with karyoskeletal protein-enriched fractions prepared from Drosophila melanogaster embryos. Results of indirect immunofluorescence experiments suggest that this protein, here designated p75, is primarily associated with puffed regions of larval salivary gland polytene chromosomes. In nonpolytenized Schneider 2 tissue culture cells, p75 appeared to be localized throughout the nuclear interior during interphase. In mitotic cells, p75 was redistributed diffusely. A possible role for karyoskeletal elements in transcriptional regulation is discussed.

scholarly journals p75, a polypeptide component of karyoskeletal protein-enriched fractions associated with transcriptionally active loci of Drosophila melanogaster polytene chromosomes.

1988 ◽  
Vol 8 (5) ◽  
pp. 1877-1886 ◽  
Author(s):  
B M Benton ◽  
S Berrios ◽  
P A Fisher
Keyword(s):  
Tissue Culture ◽  
Drosophila Melanogaster ◽  
Transcriptional Regulation ◽  
Salivary Gland ◽  
Indirect Immunofluorescence ◽  
Polytene Chromosomes ◽  
Nuclear Interior ◽  
Culture Cells ◽  
Tissue Culture Cells ◽  
Larval Salivary Gland

A 75-kilodalton polypeptide has been identified which copurifies with karyoskeletal protein-enriched fractions prepared from Drosophila melanogaster embryos. Results of indirect immunofluorescence experiments suggest that this protein, here designated p75, is primarily associated with puffed regions of larval salivary gland polytene chromosomes. In nonpolytenized Schneider 2 tissue culture cells, p75 appeared to be localized throughout the nuclear interior during interphase. In mitotic cells, p75 was redistributed diffusely. A possible role for karyoskeletal elements in transcriptional regulation is discussed.

scholarly journals The Relation between Protein Synthesis and Lipide Accumulation in L Strain Cells and Ehrlich Ascites Cells

1959 ◽  
Vol 5 (3) ◽  
pp. 421-431 ◽  
Author(s):  
Donald W. King ◽  
Edward L. Socolow ◽  
Klaus G. Bensch
Keyword(s):  
Tissue Culture ◽  
Protein Synthesis ◽  
Cell Division ◽  
Growth Period ◽  
Cholesterol Content ◽  
Cell Ratio ◽  
L Cells ◽  
Ehrlich Ascites ◽  
Ehrlich Ascites Cells

It has long been known that fat accumulates in old injured cells both in tissue culture and in many mammalian disease states. The use of L cells grown in suspension tissue culture permitted the opportunity to study conditions in which lipide accumulation could be retarded or accelerated. These cultures exhibit a three-phase growth curve which is similar to that previously found with bacteria and consists of a lag period, logarithmic growth period, and stationary period. Daily aliquots were removed from cultures going through these phases and protein and cholesterol content correlated with cell division. It was found that L cells gradually accumulated lipide in the cell concurrent with retardation of cell division and protein synthesis. Conversely old lipide-laden cells, placed in fresh media and encouraged to active division with net protein synthesis progressed from a high to a low lipide/cell ratio over a period of 2 to 4 days. An amino acid analogue p-fluorophenylalanine and a mitotic inhibitor, colchicine, also markedly increased the lipide/cell ratio. Similar results were found in in vitro experiments with Ehrlich ascites cells.

scholarly journals In situ hybridization analysis of chromosomal homologies in Drosophila melanogaster and Drosophila virilis.

Genetics ◽  
1989 ◽  
Vol 122 (1) ◽  
pp. 99-109 ◽  
Author(s):  
J H Whiting ◽  
M D Pliley ◽  
J L Farmer ◽  
D E Jeffery
Keyword(s):  
Drosophila Melanogaster ◽  
Salivary Gland ◽  
In Situ Hybridization ◽  
Recombinant Dna ◽  
Unique Sequence ◽  
Drosophila Virilis ◽  
Multigene Families ◽  
Larval Salivary Gland ◽  
Chromosomal Homologies

Abstract Twenty-four biotin-labeled recombinant-DNA probes which contained putative unique-sequence Drosophila melanogaster DNA were hybridized to larval salivary-gland chromosomes of D. melanogaster and Drosophila virilis. All probes hybridized to D. melanogaster chromosomes at the expected sites. However, one probe hybridized to at least 16 additional sites, and one hybridized to one additional site. Thirteen probes hybridized strongly to D. virilis chromosomes, four hybridized weakly and infrequently, and seven did not hybridize. Probes representing two multigene families (beta-tubulin and yolk-protein) hybridized as would be expected if all sites had been conserved in the two species on the same chromosomal elements. The multiple hybridization sites of a third probe which may represent a multigene family were also conserved. The results were consistent with H.J. Muller's proposal that chromosomal elements have been conserved during evolution of this genus.

scholarly journals Effect of Sewage Sludge Compost Usage on Corn and Faba Bean Growth, Carbon and Nitrogen Forms in Plants and Soil

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 628
Author(s):  
Hassan E. Abd Elsalam ◽  
Mohamed E. El- Sharnouby ◽  
Abdallah E. Mohamed ◽  
Bassem M. Raafat ◽  
Eman H. El-Gamal
Keyword(s):  
Organic Matter ◽  
Sewage Sludge ◽  
Plant Growth ◽  
Total Nitrogen ◽  
Faba Bean ◽  
Residual Effect ◽  
Growth Period ◽  
Nitrogen Forms ◽  
Amended Soils ◽  
Nitrogen Levels

Sewage sludge is an effective fertilizer in many soil types. When applied as an amendment, sludge introduces, in addition to organic matter, plant nutrients into the soil. When applied for cropland as a fertilizer, the mass loading of sewage sludge is customarily determined by inputs of N and/or P required to support optimal plant growth and a successful harvest. This study aims to examine the changes in organic matter contents and nitrogen forms in sludge-amended soils, as well as the growth of corn and faba bean plants. The main results indicated that there were higher responses to the corn and faba bean yields when sludge was added. Levels of organic carbon in soil were higher after maize harvest and decreased significantly after harvesting of beans, and were higher in sludge amended soils than unmodified soils, indicating the residual effect of sludge in soil. NO3−-N concentrations were generally higher in the soil after maize harvest than during the plant growth period, but this trend was not apparent in bean soil. The amounts of NH4+-N were close in the soil during the growth period or after the maize harvest, while they were higher in the soil after the bean harvest than they were during the growth period. Total nitrogen amounts were statistically higher in the soil during the growth period than those collected after the corn harvest, while they were approximately close in the bean soil. The total nitrogen amount in corn and bean leaves increased significantly in plants grown on modified sludge soil. There were no significant differences in the total nitrogen levels of the maize and beans planted on the treated soil.

Sign in / Sign up

Export Citation Format

Share Document