Retrotransposon-induced ectopic expression of cut causes the Om(1A) mutant in Drosophila ananassae.

Genetics ◽  
1994 ◽  
Vol 137 (1) ◽  
pp. 165-174
Author(s):  
T Awasaki ◽  
N Juni ◽  
T Hamabata ◽  
K Yoshida ◽  
M Matsuda ◽  
...  
Keyword(s):  
Cell Death ◽  
Gamma Ray ◽  
Ectopic Expression ◽  
Inducible Promoter ◽  
Imaginal Discs ◽  
Drosophila Ananassae ◽  
Cut Locus ◽  
Coding Region ◽  
Dna Fragment ◽  
Om Mutations

Abstract Optic morphology (Om) mutations in Drosophila ananassae map to at least 22 loci scattered throughout the genome. They are semidominant, neomorphic, nonpleiotropic, and are associated with the insertion of a retrotransposon, tom. The Om(1A) gene, which is cytogenetically linked to the cut locus, was cloned using a DNA fragment of the cut locus of Drosophila melanogaster as a probe. Three of the eight alleles of Om(1A) examined have insertion of the tom element within a putative cut region. The gamma-ray-induced revertants of Om(1A) are accompanied with cut lethal mutations and rearrangements within the cut coding region. In the eye imaginal discs of the Om(1A) mutants, differentiation of photoreceptor clusters is suppressed, abnormal cell death occurs in the center and the cut protein is expressed ectopically. D. melanogaster flies transformed with a chimeric cut gene under the control of a heat-inducible promoter show excessive cell death in the region anterior to the morphogenetic furrow, suppressed differentiation to photoreceptor clusters and defect in the imaginal eye morphology when subjected to temperature elevation. These findings suggest that the tom element inserted within the Om(1A) region induces ectopic cut expression in the eye imaginal discs, thus resulting in the Om(1A) mutant phenotype.

scholarly journals Apoptosis and in vivo models to study the molecules related to this phenomenon

2010 ◽  
Vol 8 (4) ◽  
pp. 495-497 ◽  
Author(s):  
Adriana Luchs ◽  
Claudia Pantaleão
Keyword(s):  
Cell Death ◽  
B Cell ◽  
Ectopic Expression ◽  
B Cell Lymphoma ◽  
Murine Models ◽  
In Vivo Models ◽  
Large B Cell Lymphoma ◽  
Pathological Conditions ◽  
Pharmacological Targets

ABSTRACT Apoptosis or programmed cell death is a physiological process, essential for eliminating cells in excess or that are no longer necessary to the organism, acting on tissue homeostasis, although the phenomenon is also involved in pathological conditions. Apoptosis promotes activation of biochemical pathways inside cells called caspase pathway, of the proteins responsible for the cleavage of several cell substrates, leading to cell death. Antiapoptotic members of the Bcl-2 family (B cell CLL/lymphoma 2), that belong to the intrinsic route of the activation of caspases, such as Bcl-xL (extra-large B-cell lymphoma) and Bcl-w (Bcl-2-like 2), act predominantly to prevent that pro-apoptotic members, such as Bax (Bcl-2-associated X protein) and Bak (Bcl-2 relative bak) lead to cell death. Antiapoptotic molecules are considered potentially oncogenic. Murine models are known to be valuable systems for the experimental analysis of oncogenes in vivo, and for the identification of pharmacological targets for cancer and to assess antitumor therapies. Given the importance of tumorigenesis studies on the immune responses to cancer and the possibility of investigating the participation of antiapoptotic molecules in tumor progression in vivo, the development of new models may be platforms for studies on tumorigenesis, immune antitumor responses, investigation of the ectopic expression of antiapoptotic molecules and immunotherapies for tumors.

scholarly journals Insertion of the βGeo Promoter Trap into the Fem1c Gene of ROSA3 Mice

2004 ◽  
Vol 24 (9) ◽  
pp. 3794-3803 ◽  
Author(s):  
Cassandra L. Schlamp ◽  
Andrew T. Thliveris ◽  
Yan Li ◽  
Louis P. Kohl ◽  
Claudia Knop ◽  
...  
Keyword(s):  
Cell Death ◽  
Ganglion Cells ◽  
Neuronal Cell Death ◽  
Insertion Site ◽  
Neuronal Cell ◽  
Pyramidal Cells ◽  
Coding Region ◽  
Protein Levels ◽  
Molecular Events ◽  
Promoter Trap

ABSTRACT ROSA3 mice were developed by retroviral insertion of the βGeo gene trap vector. Adult ROSA3 mice exhibit widespread expression of the trap gene in epithelial cells found in most organs. In the central nervous system the highest expression of βGeo is found in CA1 pyramidal cells of the hippocampus, Purkinje cells of the cerebellum, and ganglion cells of the retina. Characterization of the genomic insertion site for βGeo in ROSA3 mice shows that the trap vector is located in the first intron of Fem1c, a gene homologous to the sex-determining gene fem-1 of Caenorhabditis elegans. Transcription of the Rosa3 allele (R3) yields a spliced message that includes the first exon of Fem1c and the βGeo coding region. Although normal processing of the Fem1c transcript is disrupted in homozygous Rosa3 (Fem1cR3/R3 ) mice, some tissues show low levels of a partially processed transcript containing exons 2 and 3. Since the entire coding region of Fem1c is located in these two exons, Fem1cR3/R3 mice may still be able to express a putative FEM1C protein. To this extent, Fem1cR3/R3 mice show no adverse effects in their sexual development or fertility or in the attenuation of neuronal cell death, another function that has been attributed to both fem-1 and a second mouse homolog, Fem1b. Examination of βGeo expression in ganglion cells after exposure to damaging stimuli indicates that protein levels are rapidly depleted prior to cell death, making the βGeo reporter gene a potentially useful marker to study early molecular events in damaged neurons.

scholarly journals OM MUTATIONS IN DROSOPHILA ANANASSAE ARE LINKED TO INSERTIONS OF A TRANSPOSABLE ELEMENT

Genetics ◽  
1986 ◽  
Vol 114 (1) ◽  
pp. 125-135
Author(s):  
Antony E Shrimpton ◽  
Elizabeth A Montgomery ◽  
Charles H Langley
Keyword(s):  
In Situ Hybridization ◽  
Genetic Mapping ◽  
Transposable Element ◽  
Southern Blotting ◽  
Spontaneous Mutation ◽  
Drosophila Ananassae ◽  
Homologous Region ◽  
Eye Morphology ◽  
Om Mutations

ABSTRACT It has been hypothesized that Om mutability in Drosophila ananassae (involving spontaneous mutation at 20 loci, resulting in semidominant, nonpleiotropic eye morphology defects) was due to insertion of a transposable element, tom. One particularly unstable Χ-linked Om allele produced several derivatives, one of which has a more extreme Om phenotype and was accompanied by a singed bristle mutant, sn9g. DNA probes from the sn locus of D. melanogaster were used to clone the homologous region of D. ananassae. Analysis of sn9g DNA detected a 6.5-kb insert. Genomic Southern blotting and in situ hybridization techniques showed that this insert is repetitive and dispersed. The existence of the tom element is supported by genetic mapping that established homology between the 6.5-kb sn9g insert and Om mutants at the four Χ-linked loci tested.

scholarly journals KERAGAMAN GENETIK MUTAN M-2 CABAI MERAH KERITING (Capsicum annuum L.) BERDASARKAN PENANDA RAPD

2020 ◽  
Vol 10 (2) ◽  
pp. 92
Author(s):  
Rosmaina Rosmaina ◽  
Dedi Mulyadi ◽  
Rita Elfianis ◽  
Zulfahmi Zulfahmi
Keyword(s):  
Capsicum Annuum ◽  
Gamma Ray ◽  
Rapd Analysis ◽  
Genetic Material ◽  
Polymorphic Loci ◽  
Capsicum Annuum L ◽  
Horticultural Plant ◽  
Dna Fragment ◽  
And Control ◽  
Selection Of

Chili is an important horticultural plant in Indonesia. This research aims to carry out RAPD analysis on Mutant M2 of chili pepper (Capsicum annuum L.). Six M2 genotypes of chili irradiated by gamma ray and control plants were amplified by 16 random primers. The amplification results of M2 chili with 16 primers produced 118 loci, with fragment sizes ranging from 150-2000 bp. The number of polymorphic loci was 96 loci and the percentage of polymorphic loci was 83.23%. The DNA fragment polymorphism produced in this research was relatively high and it showed that the gamma ray mutagen applied produced high chili genetic diversity. The value of genetic similarity between control plants and mutant plants ranged from 0.7474 to 0.4874. UPGMA dendogram classified seven genotypes tested into three groups, the first group consisted of mutants R2U6 and R2U17, the second group was mutants R1U14 and R1U17, and the third group was mutants R2U8, mutants R2U2 and control plants. The finding of this research can be used as a basic selection of genetic material for chili’s breeding in the future.

The Serrate locus of Drosophila and its role in morphogenesis of the wing imaginal discs: control of cell proliferation

Development ◽  
1994 ◽  
Vol 120 (3) ◽  
pp. 535-544 ◽  
Author(s):  
S.A. Speicher ◽  
U. Thomas ◽  
U. Hinz ◽  
E. Knust
Keyword(s):  
Cell Proliferation ◽  
Transmembrane Protein ◽  
Ectopic Expression ◽  
Imaginal Discs ◽  
Specific Cell ◽  
Loss Of Function ◽  
Severe Reduction ◽  
Homozygous Mutant ◽  
Wing Imaginal Discs ◽  
Larval Lethality

The Drosophila gene Serrate encodes a transmembrane protein with 14 EGF-like repeats in its extracellular domain. Here we show that loss-of-function mutations in this gene lead to larval lethality. Homozygous mutant larvae fail to differentiate the anterior spiracles, exhibit poorly developed mouth-hooks and show a severe reduction in the size of the wing and haltere primordia, which is not due to cell death. The few homozygous mutant escapers that pupariate develop into pharate adults that almost completely lack wings and halteres. Clonal analysis in the adult epidermis demonstrates a requirement for Serrate during wing and haltere development. Targeted ectopic expression of Serrate in the imaginal discs using the yeast transcriptional activator Gal4 results in regionally restricted induction of cell proliferation, e.g. the ventral tissues in the case of the wings and halteres. The results suggest that the wild-type function of Serrate is required for the control of position-specific cell proliferation during development of meso- and metathoracic dorsal discs, which in turn exerts a direct effect on morphogenesis.

Steroid regulated programmed cell death during Drosophila metamorphosis

Development ◽  
1997 ◽  
Vol 124 (22) ◽  
pp. 4673-4683 ◽  
Author(s):  
C. Jiang ◽  
E.H. Baehrecke ◽  
C.S. Thummel
Keyword(s):  
Cell Death ◽  
Salivary Gland ◽  
Programmed Cell Death ◽  
Salivary Glands ◽  
Ectopic Expression ◽  
Salivary Gland Cell ◽  
Cell Nuclei ◽  
Larval Midgut ◽  
Insect Metamorphosis ◽  
Specific Regulation

During insect metamorphosis, pulses of the steroid hormone 20-hydroxyecdysone (ecdysone) direct the destruction of obsolete larval tissues and their replacement by tissues and structures that form the adult fly. We show here that larval midgut and salivary gland histolysis are stage-specific steroid-triggered programmed cell death responses. Dying larval midgut and salivary gland cell nuclei become permeable to the vital dye acridine orange and their DNA undergoes fragmentation, indicative of apoptosis. Furthermore, the histolysis of these tissues can be inhibited by ectopic expression of the baculovirus anti-apoptotic protein p35, implicating a role for caspases in the death response. Coordinate stage-specific induction of the Drosophila death genes reaper (rpr) and head involution defective (hid) immediately precedes the destruction of the larval midgut and salivary gland. In addition, the diap2 anti-cell death gene is repressed in larval salivary glands as rpr and hid are induced, suggesting that the death of this tissue is under both positive and negative regulation. Finally, diap2 is repressed by ecdysone in cultured salivary glands under the same conditions that induce rpr expression and trigger programmed cell death. These studies indicate that ecdysone directs the death of larval tissues via the precise stage- and tissue-specific regulation of key death effector genes.

The Branchless Gene C lbl in Watermelon Encoding a Terminal Flower 1 Protein Regulate S the Number of Lateral Branch

2021 ◽  
Author(s):  
Junling Dou ◽  
Huihui Yang ◽  
Dongling Sun ◽  
Sen Yang ◽  
Shouru Sun ◽  
...  
Keyword(s):  
Ectopic Expression ◽  
Recessive Gene ◽  
Crop Productivity ◽  
Lateral Branch ◽  
Coding Region ◽  
Terminal Flower ◽  
Apical Bud ◽  
Terminal Flower 1 ◽  
Branch Development ◽  
Lateral Branches

Abstract Lateral branching is one of the most important traits, which directly determines plant 27 architecture and crop productivity. Commercial watermelon has the characteristics of multiple 28 lateral branches, and it is time-consuming and labor costing to manually remove the lateral 29 branches in traditional watermelon cultivation. In our present study, a lateral branchless trait was 30 identified in watermelon material W CZ, and genetic analysis revealed that it was controlled by a 31 single recessive gene, which named as Clbl . A bulked segregant sequencing (BSA seq) and 32 linkage analysis was conducted to primarily mapping of Clbl on watermelon chromosome 4 33 Next-generation sequencing aided marker discovery and a large mapping population consisting of 34 1406 F 2 plants was used to further mapped the Clbl locus into a 9011 bp candidate region which 35 harbored only one candidate gene Cla018392 encoding a TERMINAL FLOWER 1 gene. Sequence 36 comparison of Cla018392 between two parental lines revealed that there was a SNP detected from 37 C to A in the coding region in the branchless inbred line WCZ , which resulted in a mutation of 38 Alanine (GCA) to Glutamate (GAA) at the fourth exon A dCAPS marker was developed from the 39 SNP locus, which was co-segregated with the branchless phenotype in both BC 1 and F 2 population, 40 and it was also further validated in 152 natural watermelon accessions. qRT PCR and in situ 41 hybridization showed that the expression levels of Cla0 18392 was significantly reduced in the 42 axillary bud and apical bud in the branchless line WCZ Ectopic expression of ClTFL1 in 43 Arabidopsis showed an increased number of lateral branches. The results of this study will be 44 useful for better understanding the molecular mechanism of lateral branch development in 45 watermelon and for the development of marker-assisted selection (MAS) for new branchless 46 watermelon cultivars.

Ectopic engrailed 1 expression in the dorsal midline causes cell death, abnormal differentiation of circumventricular organs and errors in axonal pathfinding

Development ◽  
2000 ◽  
Vol 127 (18) ◽  
pp. 4061-4071 ◽  
Author(s):  
A. Louvi ◽  
M. Wassef
Keyword(s):  
Cell Death ◽  
Choroid Plexus ◽  
Subcommissural Organ ◽  
Ectopic Expression ◽  
Axonal Pathfinding ◽  
Posterior Commissure ◽  
Expression Domain ◽  
In Ovo ◽  
Dorsal Midline ◽  
Endogenous Expression

A series of gain- or loss-of-function experiments performed in different vertebrate species have demonstrated that the Engrailed genes play multiple roles during brain development. In particular, they have been implicated in the determination of the mid/hindbrain domain, in cell proliferation and survival, in neurite formation, tissue polarization and axonal pathfinding. We have analyzed the consequences of a local gain of En function within or adjacent to the endogenous expression domain in mouse and chick embryos. In WEXPZ.En1 transgenic mice (Danielian, P. S. and McMahon, A. P. (1996) Nature 383, 332–334) several genes are induced as a consequence of ectopic expression of En1 in the diencephalic roof (but in a pattern inconsistent with a local di- to mes-encephalon fate change). The development of several structures with secretory function, generated from the dorsal neuroepithelium, is severely compromised. The choroid plexus, subcommissural organ and pineal gland either fail to form or are atrophic. These defects are preceded by an increase in cell death at the dorsal midline. Comparison with the phenotype of Wnt1(sw/sw) (swaying) mutants suggests that subcommissural organ failure is the main cause of prenatal hydrocephalus observed in both strains. The formation of the posterior commissure is also delayed, and errors in axonal pathfinding are frequent. In chick, ectopic expression of En by in ovo electroporation, affects growth and differentiation of the choroid plexus.

Wingless induces transdetermination in developing Drosophila imaginal discs

Development ◽  
1995 ◽  
Vol 121 (5) ◽  
pp. 1263-1272 ◽  
Author(s):  
L. Maves ◽  
G. Schubiger
Keyword(s):  
Molecular Level ◽  
Ectopic Expression ◽  
Imaginal Discs ◽  
Developmental Studies ◽  
New Approach ◽  
Cell Determination ◽  
Disc Cells ◽  
The Subject ◽  
Insight Into

Drosophila imaginal discs, the precursors of the adult fly appendages, have been the subject of intensive developmental studies, particularly on cell determination. Cultured disc fragments are recognized not only for the ability to maintain their determined state through extra cell divisions but also for the ability to transdetermine, or switch to the determined state of a different disc. An understanding of transdetermination at a molecular level will provide further insight into the requirements for maintaining cell determination. We find that ectopic expression of the Drosophila gene wingless induces transdetermination of foreleg imaginal disc cells to wing cells. This transdetermination occurs in foreleg discs of developing larvae without disc fragmentation. The in situ-transdetermining cells localize to the dorsal region of the foreleg disc. This wingless-induced transdetermination event is remarkably similar to the leg-to-wing switch that occurs after leg disc culture. Thus we have identified a new approach to a molecular dissection of transdetermination.

Distinct Apoptotic Responses Imparted by c-myc and max

Blood ◽  
1998 ◽  
Vol 92 (3) ◽  
pp. 1003-1010 ◽  
Author(s):  
Chadd E. Nesbit ◽  
Saijun Fan ◽  
Hong Zhang ◽  
Edward V. Prochownik
Keyword(s):  
Cell Death ◽  
Cell Lines ◽  
Ectopic Expression ◽  
Drug Induced ◽  
Enhanced Sensitivity ◽  
Contrast Enhanced ◽  
Apoptotic Pathways ◽  
American Society ◽  
Induced Apoptosis ◽  
Cytokine Deprivation

Abstract The c-myc oncoprotein accelerates programmed cell death (apoptosis) after growth factor deprivation or pharmacological insult in many cell lines. We have shown that max, the obligate c-myc heterodimeric partner protein, also promotes apoptosis after serum withdrawal in NIH3T3 fibroblasts or cytokine deprivation in interleukin-3 (IL-3)-dependent 32D murine myeloid cells. We now show that c-myc– and max-overexpressing 32D cells differ in the nature of their apoptotic responses after IL-3 removal or treatment with chemotherapeutic compounds. In the presence of IL-3, c-myc overexpression enhances the sensitivity of 32D cells to Etoposide (Sigma, St Louis, MO), Adriamycin (Pharmacia, Columbus, OH), and Camptothecin (Sigma), whereas max overexpression increases sensitivity only to Camptothecin. Drug treatment of c-myc–overexpressing cells in the absence of IL-3 did not alter the spectrum of drug sensitivity other than to additively accelerate cell death. In contrast, enhanced sensitivity to Adriamycin, Etoposide, and Taxol (Bristol-Meyers Squibb, Princeton, NJ) was revealed in max-overexpressing cells concurrently deprived of IL-3. Differential rates of apoptosis were not strictly correlated with the ability of the drugs to promote G1 or G2/M arrest. Ectopic expression of Bcl-2 or Bcl-XL blocked drug-induced apoptosis in both cell lines. In contrast, whereas Bcl-2 blocked apoptosis in both cell lines in response to IL-3 withdrawal, Bcl-XL blocked apoptosis in max-overexpressing cells but not in c-myc–overexpressing cells. These results provide mechanistic underpinnings for the idea that c-myc and max modulate distinct apoptotic pathways. © 1998 by The American Society of Hematology.

Sign in / Sign up

Export Citation Format

Share Document