scholarly journals Alterations in the Polypyrimidine Sequence Affect the in vitro Splicing Reactions Catalyzed by HeLa cell-Free Preparations

1989 ◽  
Vol 264 (25) ◽  
pp. 14631-14637
Author(s):  
G A Freyer ◽  
J P O'Brien ◽  
J Hurwitz
Keyword(s):  
Hela Cell ◽  
In Vitro Splicing

scholarly journals Pre-mRNA splicing and the nuclear matrix.

1987 ◽  
Vol 7 (1) ◽  
pp. 111-120 ◽  
Author(s):  
S Zeitlin ◽  
A Parent ◽  
S Silverstein ◽  
A Efstratiadis
Keyword(s):  
Hela Cell ◽  
Nuclear Matrix ◽  
Globin Gene ◽  
Mrna Splicing ◽  
Micrococcal Nuclease ◽  
Northern Analysis ◽  
Ribonucleoprotein Complexes ◽  
In Vitro Splicing

We examined the relationship between pre-mRNA splicing and the nuclear matrix by using an in vivo system that we have developed. Plasmids containing the inducible herpesvirus tk gene promoter linked to an intron-containing segment of the rabbit beta-globin gene were transfected into HeLa cells, and then the promoter was transactivated by infection with a TK- virus. Northern analysis revealed that the globin pre-mRNA and all its splicing intermediates and products are associated with the nuclear matrix prepared from such transfected cells. When the nuclear matrix was incubated with a HeLa cell in vitro splicing extract in the presence of ATP, the amount of matrix-associated precursor progressively decreased without a temporal lag in the reaction, with a corresponding increase in free intron lariat. Thus, most of the events of the splicing process (endonucleolytic cuts and branching) occur in this in vitro complementation reaction. However, ligation of exons cannot be monitored in this system because of the abundance of preexisting mature mRNA. Since the matrix is not a self-splicing entity, whereas the in vitro splicing system cannot process efficiently deproteinized matrix RNA, we conclude from our in vitro complementation results (which can be reproduced by using micrococcal nuclease-treated splicing extract) that the nuclear matrix preparation retains parts of preassembled ribonucleoprotein complexes that have the potential to function when supplemented with soluble factors (presumably other than most of the small nuclear ribonucleoproteins known to participate in splicing) present in the HeLa cell extract.

Pre-mRNA splicing and the nuclear matrix

1987 ◽  
Vol 7 (1) ◽  
pp. 111-120
Author(s):  
S Zeitlin ◽  
A Parent ◽  
S Silverstein ◽  
A Efstratiadis
Keyword(s):  
Hela Cell ◽  
Nuclear Matrix ◽  
Globin Gene ◽  
Mrna Splicing ◽  
Micrococcal Nuclease ◽  
Northern Analysis ◽  
Ribonucleoprotein Complexes ◽  
In Vitro Splicing

We examined the relationship between pre-mRNA splicing and the nuclear matrix by using an in vivo system that we have developed. Plasmids containing the inducible herpesvirus tk gene promoter linked to an intron-containing segment of the rabbit beta-globin gene were transfected into HeLa cells, and then the promoter was transactivated by infection with a TK- virus. Northern analysis revealed that the globin pre-mRNA and all its splicing intermediates and products are associated with the nuclear matrix prepared from such transfected cells. When the nuclear matrix was incubated with a HeLa cell in vitro splicing extract in the presence of ATP, the amount of matrix-associated precursor progressively decreased without a temporal lag in the reaction, with a corresponding increase in free intron lariat. Thus, most of the events of the splicing process (endonucleolytic cuts and branching) occur in this in vitro complementation reaction. However, ligation of exons cannot be monitored in this system because of the abundance of preexisting mature mRNA. Since the matrix is not a self-splicing entity, whereas the in vitro splicing system cannot process efficiently deproteinized matrix RNA, we conclude from our in vitro complementation results (which can be reproduced by using micrococcal nuclease-treated splicing extract) that the nuclear matrix preparation retains parts of preassembled ribonucleoprotein complexes that have the potential to function when supplemented with soluble factors (presumably other than most of the small nuclear ribonucleoproteins known to participate in splicing) present in the HeLa cell extract.

Effect of black seeds (Nigella sativa) volatile oil on the cervical cancer: In vitro study, on Hela cell lines

2019 ◽  
Vol 7 (4) ◽  
pp. 91-96
Author(s):  
Isra'a Al-sobhi ◽  
◽  
Rawan Al-Ghabban ◽  
Soad Shaker Ali ◽  
Jehan Al-Amri ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Hela Cell ◽  
Cell Lines ◽  
Nigella Sativa ◽  
In Vitro Study ◽  
Volatile Oil ◽  
Vitro Study ◽  
Hela Cell Lines ◽  
Black Seeds

Design and synthesis of herboxidiene derivatives that potently inhibit in vitro splicing

2021 ◽  
Vol 19 (6) ◽  
pp. 1365-1377
Author(s):  
Arun K. Ghosh ◽  
Srinivasa Rao Allu ◽  
Guddeti Chandrashekar Reddy ◽  
Adriana Gamboa Lopez ◽  
Patricia Mendez ◽  
...  
Keyword(s):  
Biological Evaluation ◽  
Design And Synthesis ◽  
In Vitro Splicing ◽  
Enantioselective Syntheses ◽  
Derivatives Of

Enantioselective syntheses of C-6 modified derivatives of herboxidiene and their biological evaluation in splicing inhibitory assay.

Interaction of Candida albicans with genital mucosa: effect of sex hormones on adherence of yeasts in vitro

1988 ◽  
Vol 34 (3) ◽  
pp. 224-228 ◽  
Author(s):  
Aliza Kalo ◽  
Esther Segal
Keyword(s):  
Candida Albicans ◽  
Hela Cell ◽  
Sex Hormones ◽  
Hela Cells ◽  
Cell Types ◽  
Vaginal Candidiasis ◽  
Genital Mucosa ◽  
Hela Cell Lines ◽  
I Cells

Findings from our previous studies revealed a correlation between the level of adherence in vitro of Candida albicans to human exfoliated vaginal epithelial cells (VEC) and the hormonal status of the cell donors. In the present study we investigated the effect of the sex hormones estradiol, estriol, progesterone, and testosterone on the binding of the yeasts to HeLa cell lines and VEC in vitro. Monolayers of HeLa cells were exposed to the hormones and yeasts under controlled conditions. The number of adherent yeasts per square millimetre of HeLa cell monolayers and the percentage of VEC with adherent yeasts was estimated by microscopic counts. The results showed that the tested sex hormones affected at various degrees the adhesion of yeasts to HeLa cells or VEC. Progesterone had the most marked effect, leading to a significant increase in the number of adherent yeasts to HeLa cells or in the percentage of adhesion of VEC. In addition, VEC were separated on Percoll gradients into the two cell types: superficial (S) and intermediate (I), cell types which appear physiologically under increased serum levels of estradiol or progesterone, respectively. Adhesion assays with the separated cell populations revealed an increased binding capacity of the I cells. The finding that progesterone increased the adherence of yeasts to genital mucosa and that VEC of the I type have a higher capacity to adhere the yeasts is compatible with our previous observation that increased numbers of I cells, appearing under high level of progesterone, are found in situations known to have predisposition to vaginal candidiasis. Thus, our data point to a possible involvement of the hormone progesterone in the adherence of C. albicans to genital epithelium.

scholarly journals CP30, a Cysteine Proteinase Involved inTrichomonas vaginalis Cytoadherence

2000 ◽  
Vol 68 (9) ◽  
pp. 4907-4912 ◽  
Author(s):  
M. Remedios Mendoza-López ◽  
Cecilia Becerril-Garcia ◽  
Loriz V. Fattel-Facenda ◽  
Leticia Avila-Gonzalez ◽  
Martha E. Ruíz-Tachiquín ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Hela Cell ◽  
Trichomonas Vaginalis ◽  
Cysteine Proteinase ◽  
Collagen Iv ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Cell Monolayers ◽  
Thiol Proteinase

ABSTRACT We describe here the participation of a Trichomonas vaginalis 30-kDa proteinase (CP30) with affinity to the HeLa cell surface in attachment of this parasite to host epithelial cells. The CP30 band is a cysteine proteinase because its activity was inhibited by E-64, a thiol proteinase inhibitor. In two-dimensional substrate gel electrophoresis of total extracts of the trichomonad isolate CNCD 147, three spots with proteolytic activity were detected in the 30-kDa region, in the pI range from 4.5 to 5.5. Two of the spots (pI 4.5 and 5.0) bound to the surfaces of fixed HeLa cells corresponding to the CP30 band. The immunoglobulin G fraction of the rabbit anti-CP30 antiserum that recognized a 30-kDa band by Western blotting and immunoprecipitated CP30 specifically inhibited trichomonal cytoadherence to HeLa cell monolayers in a concentration-dependent manner and reacted with CP30 at the parasite surface. CP30 degraded proteins found on the female urogenital tract, including fibronectin, collagen IV, and hemoglobin. Interestingly, CP30 digested fibronectin and collagen IV only at pH levels between 4.5 and 5.0. Moreover, trichomonosis patients whose diagnosis was confirmed by in vitro culture possessed antibody to CP30 in both sera and vaginal washes, and CP30 activity was found in vaginal washes. Our results suggest that surface CP30 is a cysteine proteinase necessary for trichomonal adherence to human epithelial cells.

The AAUAAA sequence is required both for cleavage and for polyadenylation of simian virus 40 pre-mRNA in vitro

1986 ◽  
Vol 6 (7) ◽  
pp. 2317-2323
Author(s):  
D Zarkower ◽  
P Stephenson ◽  
M Sheets ◽  
M Wickens
Keyword(s):  
Hela Cell ◽  
Simian Virus 40 ◽  
Nuclear Extract ◽  
Simian Virus ◽  
Polyadenylation Site ◽  
Single Base ◽  
Cleavage And Polyadenylation ◽  
Cell Nuclear Extract

The sequence AAUAAA is found near the polyadenylation site of eucaryotic mRNAs. This sequence is required for accurate and efficient cleavage and polyadenylation of pre-mRNAs in vivo. In this study we show that synthetic simian virus 40 late pre-mRNAs are cleaved and polyadenylated in vitro in a HeLa cell nuclear extract, and that cleavage in vitro is abolished by each of four different single-base changes in AAUAAA. In this same extract, precleaved RNAs (RNAs with 3' termini at the polyadenylation site) are efficiently polyadenylated. This in vitro polyadenylation reaction also requires the AAUAAA sequence.

Sign in / Sign up

Export Citation Format

Share Document