scholarly journals Reduced expression of CDP-DAG synthase changes lipid composition and leads to male sterility in Drosophila

Open Biology ◽  
2016 ◽  
Vol 6 (1) ◽  
pp. 150169 ◽  
Author(s):  
Barbara Laurinyecz ◽  
Mária Péter ◽  
Viktor Vedelek ◽  
Attila L. Kovács ◽  
Gábor Juhász ◽  
...  
Keyword(s):  
Phosphatidic Acid ◽  
Lipid Composition ◽  
Transcriptional Activity ◽  
Gene Products ◽  
Small Reduction ◽  
Male Sterile ◽  
Ideal System ◽  
Sperm Development ◽  
Late Stages ◽  
Membrane Biosynthesis

Drosophila spermatogenesis is an ideal system to study the effects of changes in lipid composition, because spermatid elongation and individualization requires extensive membrane biosynthesis and remodelling. The bulk of transcriptional activity is completed with the entry of cysts into meiotic division, which makes post-meiotic stages of spermatogenesis very sensitive to even a small reduction in gene products. In this study, we describe the effect of changes in lipid composition during spermatogenesis using a hypomorphic male sterile allele of the Drosophila CDP-DAG synthase ( CdsA ) gene. We find that the CdsA mutant shows defects in spermatid individualization and enlargement of mitochondria and the axonemal sheath of the spermatids. Furthermore, we could genetically rescue the male sterile phenotype by overexpressing Phosphatidylinositol synthase (dPIS) in a CdsA mutant background. The results of lipidomic and genetic analyses of the CdsA mutant highlight the importance of correct lipid composition during sperm development and show that phosphatidic acid levels are crucial in late stages of spermatogenesis.

Dimerization through the helix-loop-helix motif enhances phosphorylation of the transcription activation domains of myogenin

1994 ◽  
Vol 14 (9) ◽  
pp. 6232-6243
Author(s):  
J Zhou ◽  
E N Olson
Keyword(s):  
Transcriptional Activity ◽  
Transcription Activation ◽  
Bhlh Protein ◽  
Specific Gene ◽  
Phosphorylation Sites ◽  
Gene Products ◽  
Activation Domains ◽  
Helix Loop Helix ◽  
Carboxyl Terminal ◽  
Bhlh Proteins

The muscle-specific basic helix-loop-helix (bHLH) protein myogenin activates muscle transcription by binding to target sequences in muscle-specific promoters and enhancers as a heterodimer with ubiquitous bHLH proteins, such as the E2A gene products E12 and E47. We show that dimerization with E2A products potentiates phosphorylation of myogenin at sites within its amino- and carboxyl-terminal transcription activation domains. Phosphorylation of myogenin at these sites was mediated by the bHLH region of E2A products and was dependent on dimerization but not on DNA binding. Mutations of the dimerization-dependent phosphorylation sites resulted in enhanced transcriptional activity of myogenin, suggesting that their phosphorylation diminishes myogenin's transcriptional activity. The ability of E2A products to potentiate myogenin phosphorylation suggests that dimerization induces a conformational change in myogenin that unmasks otherwise cryptic phosphorylation sites or that E2A proteins recruit a kinase for which myogenin is a substrate. That phosphorylation of these dimerization-dependent sites diminished myogenin's transcriptional activity suggests that these sites are targets for a kinase that interferes with muscle-specific gene expression.

Late stages in bacteriophage λ head morphogenesis: In vitro studies on the action of the bacteriophage λ D-gene and W-gene products

Virology ◽  
1988 ◽  
Vol 165 (1) ◽  
pp. 103-114 ◽  
Author(s):  
Roberta Perucchetti ◽  
Wendy Parris ◽  
Andrew Becker ◽  
Marvin Gold
Keyword(s):  
In Vitro Studies ◽  
Gene Products ◽  
Bacteriophage Λ ◽  
Morphogenesis In Vitro ◽  
Late Stages

scholarly journals Suppression in Drosophila: su(Hw) and su(f) gene products interact with a region of gypsy (mdg4) regulating its transcriptional activity.

1989 ◽  
Vol 8 (3) ◽  
pp. 903-911 ◽  
Author(s):  
A. M. Mazo ◽  
L. J. Mizrokhi ◽  
A. A. Karavanov ◽  
Y. A. Sedkov ◽  
A. A. Krichevskaja ◽  
...  
Keyword(s):  
Transcriptional Activity ◽  
Gene Products ◽  
F Gene

scholarly journals Dimerization through the helix-loop-helix motif enhances phosphorylation of the transcription activation domains of myogenin.

1994 ◽  
Vol 14 (9) ◽  
pp. 6232-6243 ◽  
Author(s):  
J Zhou ◽  
E N Olson
Keyword(s):  
Transcriptional Activity ◽  
Transcription Activation ◽  
Bhlh Protein ◽  
Specific Gene ◽  
Phosphorylation Sites ◽  
Gene Products ◽  
Activation Domains ◽  
Helix Loop Helix ◽  
Carboxyl Terminal ◽  
Bhlh Proteins

The muscle-specific basic helix-loop-helix (bHLH) protein myogenin activates muscle transcription by binding to target sequences in muscle-specific promoters and enhancers as a heterodimer with ubiquitous bHLH proteins, such as the E2A gene products E12 and E47. We show that dimerization with E2A products potentiates phosphorylation of myogenin at sites within its amino- and carboxyl-terminal transcription activation domains. Phosphorylation of myogenin at these sites was mediated by the bHLH region of E2A products and was dependent on dimerization but not on DNA binding. Mutations of the dimerization-dependent phosphorylation sites resulted in enhanced transcriptional activity of myogenin, suggesting that their phosphorylation diminishes myogenin's transcriptional activity. The ability of E2A products to potentiate myogenin phosphorylation suggests that dimerization induces a conformational change in myogenin that unmasks otherwise cryptic phosphorylation sites or that E2A proteins recruit a kinase for which myogenin is a substrate. That phosphorylation of these dimerization-dependent sites diminished myogenin's transcriptional activity suggests that these sites are targets for a kinase that interferes with muscle-specific gene expression.

scholarly journals Early Stages of Golgi Vesicle and Tubule Formation Require Diacylglycerol

2009 ◽  
Vol 20 (3) ◽  
pp. 780-790 ◽  
Author(s):  
Lennart Asp ◽  
Fredrik Kartberg ◽  
Julia Fernandez-Rodriguez ◽  
Maria Smedh ◽  
Markus Elsner ◽  
...  
Keyword(s):  
Rna Interference ◽  
Golgi Apparatus ◽  
Phosphatidic Acid ◽  
Golgi Vesicle ◽  
Tubule Formation ◽  
Bud Formation ◽  
Early Stages ◽  
Golgi Membranes ◽  
Phosphatidate Phosphohydrolase ◽  
Late Stages

We have investigated the role for diacylglycerol (DAG) in membrane bud formation in the Golgi apparatus. Addition of propranolol to specifically inhibit phosphatidate phosphohydrolase (PAP), an enzyme responsible for converting phosphatidic acid into DAG, effectively prevents formation of membrane buds. The effect of PAP inhibition on Golgi membranes is rapid and occurs within 3 min. Removal of the PAP inhibitor then results in a rapid burst of buds, vesicles, and tubules that peaks within 2 min. The inability to form buds in the presence of propranolol does not appear to be correlated with a loss of ARFGAP1 from Golgi membranes, as knockdown of ARFGAP1 by RNA interference has little or no effect on actual bud formation. Rather, knockdown of ARFGAP1 results in an increase in membrane buds and a decrease of vesicles and tubules suggesting it functions in the late stages of scission. How DAG promotes bud formation is discussed.

scholarly journals Exploitation of nuclear and cytoplasm variability in Hordeum chilense for wheat breeding

2011 ◽  
Vol 9 (2) ◽  
pp. 313-316 ◽  
Author(s):  
Cristina Rodríguez-Suárez ◽  
María J. Giménez ◽  
María C. Ramírez ◽  
Azahara C. Martín ◽  
Natalia Gutierrez ◽  
...  
Keyword(s):  
Abiotic Stress Tolerance ◽  
Female Parent ◽  
Wheat Breeding ◽  
Septoria Tritici Blotch ◽  
Septoria Tritici ◽  
Carotenoid Content ◽  
Hordeum Chilense ◽  
Male Sterile ◽  
Alloplasmic Lines ◽  
Ideal System

Hordeum chilense Roem. et Schultz. is a diploid wild barley native to Chile and Argentina. The high crossability of this species with other members of the Triticeae tribe promoted the development of the new species × Tritordeum Ascherson et Graebner. Hexaploid tritordeum was developed from the hybrid derived from the cross between H. chilense (used as female parent) and durum wheat. The interest of H. chilense is based on the presence of traits potentially useful for wheat breeding, including high endosperm carotenoid content, septoria tritici blotch resistance and abiotic stress tolerance. Besides, the variability at cytoplasm level is also important in this species. The development of common wheat–H. chilense alloplasmic lines (nucleus from wheat and cytoplasm from H. chilense) results in fertile or male sterile genotypes, depending on the accession donating the cytoplasm. Furthermore, these alloplasmic lines constitute an ideal system for deepening our knowledge on nuclear–cytoplasm interactions. In conclusion, H. chilense is an interesting source of variability for wheat breeding.

scholarly journals Autoregulation of the Kluyveromyces lactis pyruvate decarboxylase gene KlPDC1 involves the regulatory gene RAG3

Microbiology ◽  
2014 ◽  
Vol 160 (7) ◽  
pp. 1369-1378 ◽  
Author(s):  
Daniela Ottaviano ◽  
Chiara Micolonghi ◽  
Lorenza Tizzani ◽  
Marc Lemaire ◽  
Micheline Wésolowski-Louvel ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Nuclear Localization ◽  
Transcriptional Activity ◽  
Kluyveromyces Lactis ◽  
Regulatory Gene ◽  
Pyruvate Decarboxylase ◽  
Genetic Screen ◽  
Gene Products ◽  
Transcription Level ◽  
Autoregulatory Mechanism

In the yeast Kluyveromyces lactis, the pyruvate decarboxylase gene KlPDC1 is strongly regulated at the transcription level by different environmental factors. Sugars and hypoxia act as inducers of transcription, while ethanol acts as a repressor. Their effects are mediated by gene products, some of which have been characterized. KlPDC1 transcription is also strongly repressed by its product – KlPdc1 – through a mechanism called autoregulation. We performed a genetic screen that allowed us to select and identify the regulatory gene RAG3 as a major factor in the transcriptional activity of the KlPDC1 promoter in the absence of the KlPdc1 protein, i.e. in the autoregulatory mechanism. We also showed that the two proteins Rag3 and KlPdc1 interact, co-localize in the cell and that KlPdc1 may control Rag3 nuclear localization.

scholarly journals T(16: 17)43H translocation as a tool in analysis of the proximal part of chromosome 17 (including T-t gene complex) of the mouse

1980 ◽  
Vol 35 (2) ◽  
pp. 165-177 ◽  
Author(s):  
Jiří Forejt ◽  
Jana Čapková ◽  
Soňa Gregorová
Keyword(s):  
Male Fertility ◽  
Proximal Part ◽  
Break Point ◽  
Chromosome 17 ◽  
Gene Products ◽  
Male Sterile ◽  
Gene Markers ◽  
Sperm Membrane ◽  
In Cis ◽  
Linkage Relationships

SUMMARYLinkage relationships of three gene markers of chromosome 17, namely Brachyury (T), tufted (tf), and Histocompatibility-2 (H-2), to the break-point of T(16; 17)43H male sterile translocation were established. The following order was found: T−tf−T43H−H-2. In all cases the translocation break was found in cis to H-2k, haplotype, no recombinant being found among 218 backcross individuals examined. More than 60 viable and fertile animals trisomic for the proximal part of chromosome 17 (including T-t genetic complex) have been recovered among progeny of T43H/+ female translocation heterozygotes as a result of adjacent −2 disjunction at first meiotic division. Mutation tf has been assigned to band 17B in chromosome 17 by comparing the location of T190Ca and T43H genetic and cytological breakpoints. Recombination between centromere 17 and T43H break was reduced almost to zero in the presence of Rb(16.17)7Bnr translocation. The unexpected restoration of male fertility was observed in T43H/Rb7Bnr hybrids (T43H/+ males being completely sterile) which made it possible to prepare the first homozygotes for T43H male–sterile translocation. Direct estimation of chiasma frequencies in centromere 17−T43H region indicated an 11 cM distance between the centromere 17 and the proximal end of t12 haplotype. The significance of centromere −t (or H-2) distance on the predictable restrictions of the possible haploid manifestation of T-t or H-2 gene products on sperm membrane is discussed.

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