Ultrastructural localization of acid phosphatase in cultured cells ofDaucus carota

Planta ◽  
1969 ◽  
Vol 88 (2) ◽  
pp. 91-102 ◽  
Author(s):  
Walter Halperin
Keyword(s):  
Acid Phosphatase ◽  
Cultured Cells ◽  
Ultrastructural Localization

A deletion that includes the segment coding for the signal peptidase cleavage site delays release of Saccharomyces cerevisiae acid phosphatase from the endoplasmic reticulum

1986 ◽  
Vol 6 (2) ◽  
pp. 723-729
Author(s):  
R Haguenauer-Tsapis ◽  
M Nagy ◽  
A Ryter
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Endoplasmic Reticulum ◽  
Acid Phosphatase ◽  
Cleavage Site ◽  
Ultrastructural Localization ◽  
Signal Peptidase ◽  
Multicopy Plasmid ◽  
Wild Type ◽  
Sugar Chains ◽  
Pho5 Gene

We studied ultrastructural localization of acid phosphatase in derepressed Saccharomyces cerevisiae cells transformed with a multicopy plasmid carrying either the wild-type PHO5 gene or a PHO5 gene deleted in the region overlapping the signal peptidase cleavage site. Wild-type enzyme was located in the cell wall, as was 50% of the modified protein, which carried high-mannose-sugar chains. The remaining 50% of the protein was active and core glycosylated, and it accumulated in the endoplasmic reticulum cisternae. The signal peptide remained uncleaved in both forms. Cells expressing the modified protein exhibited an exaggerated endoplasmic reticulum with dilated lumen.

The effects of androgens and estrogens on human prostatic cells in culture

1981 ◽  
Vol 59 (9) ◽  
pp. 949-956 ◽  
Author(s):  
Robert W. Hudson
Keyword(s):  
Acid Phosphatase ◽  
Sex Steroids ◽  
Prostatic Carcinoma ◽  
Cultured Cells ◽  
Carcinoma Cells ◽  
Prostatic Tissue ◽  
Single Cell Suspension ◽  
Standard Medium ◽  
Standard Culture ◽  
Androgenic Effect

A ceil culture system has been developed in order to assess the response of human prostatic carcinoma cells to the presence of androgens and estrogens. A single cell suspension of these cells was incubated in minimum essential medium, in the absence of added sex steroids (standard culture), for 24 h. Equal aliquots of these cultured cells were incubated for a further 24–72 h in standard medium or in medium to which testosterone (T, 17.4 nM), dihydrotestosterone (DHT, 1.7 nM) or estradiol (E2, 0.36 nM) had been added. At the end of the incubations, the levels of tartrate-inhibitable acid phosphatase were compared in the standard cultures and the cultures to which sex steroids had been added.There were three patterns of response of patients' cells to the presence of androgens. From a total of 91 cell cultures, obtained from 85 patients, androgens were associated with an increased acid phosphatase production in 58. In 22 incubations, there was no androgenic effect on acid phosphatase production, and in II incubations, androgens were associated with lower enzyme levels than in the standard cultures. The qualitative effects of T and DHT were the same, but the quantitative effect of DHT was greater than that of T in those experiments in which there was a positive androgenic effect on acid phosphatase production. In 10 of 46 incubations with E2, acid phosphatase levels were lower than the standard incubations, while in 28 there was no difference in enzyme levels. In eight incubations, E2 was associated with a greater acid phosphatase production than that found in the standard cultures.In cultures of the cells from 180 men with benign prostatic hyperplasia and 5 men with normal prostatic tissue, androgens and estrogens had no effect on acid production by these cells, even at DHT concentrations of 1.7 × 10−7 M.It is concluded that prostatic carcinoma cells behave differently, in culture, in response to sex steroids, than do cells from benign hyperplastic or normal prostatic tissue.

Sign in / Sign up

Export Citation Format

Share Document