scholarly journals Mating-Type Gene Structure and Spatial Distribution of Didymella tanaceti in Pyrethrum Fields

2016 ◽  
Vol 106 (12) ◽  
pp. 1521-1529 ◽  
Author(s):  
Tamieka L. Pearce ◽  
Jason B. Scott ◽  
Frank S. Hay ◽  
Sarah J. Pethybridge
Keyword(s):  
Spatial Distribution ◽  
Mating Type ◽  
Tan Spot ◽  
Mating Types ◽  
Tanacetum Cinerariifolium ◽  
Polymerase Chain ◽  
Type Gene ◽  
Mat Genes

Tan spot of pyrethrum (Tanacetum cinerariifolium) is caused by the ascomycete Didymella tanaceti. To assess the evolutionary role of ascospores in the assumed asexual species, the structure and arrangement of mating-type (MAT) genes were examined. A single MAT1-1 or MAT1-2 idiomorph was identified in all isolates examined, indicating that the species is heterothallic. The idiomorphs were flanked upstream and downstream by regions encoding pyridoxamine phosphate oxidase-like and DNA lyase-like proteins, respectively. A multiplex MAT-specific polymerase chain reaction assay was developed and used to genotype 325 isolates collected within two transects in each of four fields in Tasmania, Australia. The ratio of isolates of each mating-type in each transect was consistent with a 1:1 ratio. The spatial distribution of the isolates of the two mating-types within each transect was random for all except one transect for MAT1-1 isolates, indicating that clonal patterns of each mating-type were absent. However, evidence of a reduced selection pressure on MAT1-1 isolates was observed, with a second haplotype of the MAT1-1-1 gene identified in 4.4% of MAT1-1 isolates. In vitro crosses between isolates with opposite mating-types failed to produce ascospores. Although the sexual morph could not be induced, the occurrence of both mating-types in equal frequencies suggested that a cryptic sexual mode of reproduction may occur within field populations.

scholarly journals Deletion of the Schizophyllum commune Aα Locus: The Roles of Aα Y and Z Mating-Type Genes

Genetics ◽  
1996 ◽  
Vol 144 (4) ◽  
pp. 1437-1444
Author(s):  
C Ian Robertson ◽  
Kirk A Bartholomew ◽  
Charles P Novotny ◽  
Robert C Ullrich
Keyword(s):  
Mating Type ◽  
Sexual Development ◽  
Schizophyllum Commune ◽  
Mating Types ◽  
Developmental Pathway ◽  
Mating Type Gene ◽  
Mating Type Genes ◽  
Regulatory Loci ◽  
Type Gene

The Aα locus is one of four master regulatory loci that determine mating type and regulate sexual development in Schizophyllum commune. We have made a plasmid containing a URA1 gene disruption of the Aα Y1 gene. Y1 is the sole Aα gene in Aα1 strains. We used the plasmid construction to produce an Aα null (i.e., AαΔ) strain by replacing the genomic Y1 gene with URA1 in an Aα1 strain. To characterize the role of the Aα genes in the regulation of sexual development, we transformed various Aα Y and Z alleles into AαΔ strains and examined the acquired mating types and mating abilities of the transformants. These experiments demonstrate that the Aα Y gene is not essential for fungal viability and growth, that a solitary Z Aα mating-type gene does not itself activate development, that Aβ proteins are sufficient to activate the A developmental pathway in the absence of Aα proteins and confirm that Y and Z genes are the sole determinants of Aα mating type. The data from these experiments support and refine our model of the regulation of A-pathway events by Y and Z proteins.

scholarly journals A PCR-based Assay for Distinguishing between A1 and A2 Mating Types of Phytophthora capsici

2017 ◽  
Vol 142 (4) ◽  
pp. 260-264
Author(s):  
Ping Li ◽  
Dong Liu ◽  
Min Guo ◽  
Yuemin Pan ◽  
Fangxin Chen ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Mating Type ◽  
Phytophthora Capsici ◽  
Mating Types ◽  
Sequence Repeat ◽  
Chain Reaction ◽  
Plant Parasite ◽  
Dna Fragment ◽  
Polymerase Chain ◽  
Microsatellite Diversity

Sexual reproduction in the plant parasite Phytophthora capsici Leonian requires the interaction of two distinct mating types, A1 and A2. Co-occurrence of these mating types can enhance the genetic diversity of P. capsici and alter its virulence or resistance characteristics. Using an intersimple sequence repeat (ISSR) screen of microsatellite diversity, we identified, cloned, and sequenced a novel 1121-base pair (bp) fragment specific to the A1 mating type of P. capsici. Primers Pcap-1 and Pcap-2 were designed from this DNA fragment to specifically detect the A1 mating type. Polymerase chain reaction (PCR) using these primers amplified an expected 997-bp fragment from known A1 mating types, but yielded a 508-bp fragment from known A2 mating types. This PCR-based assay could be adapted to accurately and rapidly detect the co-occurrence of A1 and A2 P. capsici mating types from field material.

scholarly journals Schizosaccharomyces pombe ras1 and byr1 are functionally related genes of the ste family that affect starvation-induced transcription of mating-type genes.

1990 ◽  
Vol 10 (2) ◽  
pp. 549-560 ◽  
Author(s):  
S A Nadin-Davis ◽  
A Nasim
Keyword(s):  
Gene Family ◽  
Fission Yeast ◽  
Mating Type ◽  
Growth Cycle ◽  
Yeast Cells ◽  
Null Alleles ◽  
Northern Analysis ◽  
Gene Transcript ◽  
Type Gene

We have further investigated the function of the ras1 and byr1 genes, which were previously shown to be critical for sexual differentiation in fission yeast cells. Several physiological similarities between strains containing null alleles of these genes supports the idea that ras1 and byr1 are functionally closely related. Furthermore, we have found that byr1 is allelic to ste1, one of at least 10 genes which when mutated can cause sterility. Since ras1 had previously been found to be allelic to ste5, both ras and byr genes are now clearly shown to be a part of the ste gene family, thus confirming their close functional relationship. The observation that the mating-type loci could overcome the sporulation block of ras1 and byr1 mutant strains prompted investigation of the role of the ras-byr pathway in the induction of the mating-type gene transcripts upon nitrogen starvation. By Northern analysis of RNA preparations from strains carrying wild-type or mutant ras1 alleles and grown to different stages of the growth cycle, we have shown that ras1 plays an important role in inducing the Pi transcript of the mating-type loci and the mei3 gene transcript. These observations provide a molecular basis for the role of the ste gene family, including ras1 and byr1, in meiosis and indicate that further characterization of other ste genes would be very useful for elucidating the mechanism of ras1 function in fission yeast cells.

Steroid Formation in Osteoblast-Like Cells

1998 ◽  
Vol 26 (1) ◽  
pp. 1-12 ◽  
Author(s):  
H Saito ◽  
T Yanaihara
Keyword(s):  
Cell Lines ◽  
Messenger Ribonucleic Acid ◽  
Steroid Sulphatase ◽  
Menopausal Women ◽  
Hormonal Action ◽  
Polymerase Chain ◽  
Post Menopausal ◽  
Receptor Mrnas

For preventing the reduction of bone mass in post-menopausal women, oestrogen replacement is known to be useful and the importance of sex steroids in bone metabolism in both sexes is well established. The presence of steroid-converting-enzyme activities in various osteoblast and osteoblast-like cells has been demonstrated using in vitro culture systems. In the present study, we assessed the expression of messenger ribonucleic acid (mRNA) for aromatase, steroid sulphatase, 5α-reductase, 17β-hydroxysteroid dehydrogenase (17β-HSD) and 3β-HSD by reverse transcription-polymerase chain reaction in the human osteoblast-like cell lines, MG 63 and HOS. Oestrogen, androgen and progesterone receptor mRNAs were also measured. Expression of mRNA for these enzymes and receptors was found in both cell lines without induction. From these and previous findings, we conclude that osteoblast-like cells have the capacity to form biologically potent oestrogens and androgens from peripheral circulating steroids. This may indicate an important role of bone in facilitating hormonal action.

Schizosaccharomyces pombe ras1 and byr1 are functionally related genes of the ste family that affect starvation-induced transcription of mating-type genes

1990 ◽  
Vol 10 (2) ◽  
pp. 549-560
Author(s):  
S A Nadin-Davis ◽  
A Nasim
Keyword(s):  
Gene Family ◽  
Fission Yeast ◽  
Mating Type ◽  
Growth Cycle ◽  
Yeast Cells ◽  
Null Alleles ◽  
Northern Analysis ◽  
Gene Transcript ◽  
Type Gene

We have further investigated the function of the ras1 and byr1 genes, which were previously shown to be critical for sexual differentiation in fission yeast cells. Several physiological similarities between strains containing null alleles of these genes supports the idea that ras1 and byr1 are functionally closely related. Furthermore, we have found that byr1 is allelic to ste1, one of at least 10 genes which when mutated can cause sterility. Since ras1 had previously been found to be allelic to ste5, both ras and byr genes are now clearly shown to be a part of the ste gene family, thus confirming their close functional relationship. The observation that the mating-type loci could overcome the sporulation block of ras1 and byr1 mutant strains prompted investigation of the role of the ras-byr pathway in the induction of the mating-type gene transcripts upon nitrogen starvation. By Northern analysis of RNA preparations from strains carrying wild-type or mutant ras1 alleles and grown to different stages of the growth cycle, we have shown that ras1 plays an important role in inducing the Pi transcript of the mating-type loci and the mei3 gene transcript. These observations provide a molecular basis for the role of the ste gene family, including ras1 and byr1, in meiosis and indicate that further characterization of other ste genes would be very useful for elucidating the mechanism of ras1 function in fission yeast cells.

Mating types and sexual development in filamentous ascomycetes

1997 ◽  
Vol 61 (4) ◽  
pp. 411-428 ◽  
Author(s):  
E Coppin ◽  
R Debuchy ◽  
S Arnaise ◽  
M Picard
Keyword(s):  
Mating Type ◽  
Sexual Development ◽  
Single Species ◽  
Podospora Anserina ◽  
Type Model ◽  
Mating Types ◽  
Dna Binding Domains ◽  
Binding Domains ◽  
Hormonal Signal ◽  
Mat Genes

The progress made in the molecular characterization of the mating types in several filamentous ascomycetes has allowed us to better understand their role in sexual development and has brought to light interesting biological problems. The mating types of Neurospora crassa, Podospora anserina, and Cochliobolus heterostrophus consist of unrelated and unique sequences containing one or several genes with multiple functions, related to sexuality or not, such as vegetative incompatibility in N. crassa. The presence of putative DNA binding domains in the proteins encoded by the mating-type (mat) genes suggests that they may be transcriptional factors. The mat genes play a role in cell-cell recognition at fertilization, probably by activating the genes responsible for the hormonal signal whose occurrence was previously demonstrated by physiological experiments. They also control recognition between nuclei at a later stage, when reproductive nuclei of each mating type which have divided in the common cytoplasm pair within the ascogenous hyphae. How self is distinguished from nonself at the nuclear level is not known. The finding that homothallic species, able to mate in the absence of a partner, contain both mating types in the same haploid genome has raised more issues than it has resolved. The instability of the mating type, in particular in Sclerotinia trifolorium and Botrytinia fuckeliana, is also unexplained. This diversity of mating systems, still more apparent if the yeasts and the basidiomycetes are taken into account, clearly shows that no single species can serve as a universal mating-type model.

scholarly journals Genomic and Population Analyses of the Mating Type Loci in Coccidioides Species Reveal Evidence for Sexual Reproduction and Gene Acquisition

2007 ◽  
Vol 6 (7) ◽  
pp. 1189-1199 ◽  
Author(s):  
M. Alejandra Mandel ◽  
Bridget M. Barker ◽  
Scott Kroken ◽  
Steven D. Rounsley ◽  
Marc J. Orbach
Keyword(s):  
Sexual Reproduction ◽  
Mating Type ◽  
Mating Types ◽  
Coccidioides Immitis ◽  
Genome Sequences ◽  
Valley Fever ◽  
Population Analyses ◽  
Gene Acquisition ◽  
Close Proximity

ABSTRACT Coccidioides species, the fungi responsible for the valley fever disease, are known to reproduce asexually through the production of arthroconidia that are the infectious propagules. The possible role of sexual reproduction in the survival and dispersal of these pathogens is unexplored. To determine the potential for mating of Coccidioides, we analyzed genome sequences and identified mating type loci characteristic of heterothallic ascomycetes. Coccidioides strains contain either a MAT1-1 or a MAT1-2 idiomorph, which is 8.1 or 9 kb in length, respectively, the longest reported for any ascomycete species. These idiomorphs contain four or five genes, respectively, more than are present in the MAT loci of most ascomycetes. Along with their cDNA structures, we determined that all genes in the MAT loci are transcribed. Two genes frequently found in common sequences flanking MAT idiomorphs, APN2 and COX13, are within the MAT loci in Coccidioides, but the MAT1-1 and MAT1-2 copies have diverged dramatically from each other. Data indicate that the acquisition of these genes in the MAT loci occurred prior to the separation of Coccidioides from Uncinocarpus reesii. An analysis of 436 Coccidioides isolates from patients and the environment indicates that in both Coccidioides immitis and C. posadasii, there is a 1:1 distribution of MAT loci, as would be expected for sexually reproducing species. In addition, an analysis of isolates obtained from 11 soil samples demonstrated that at three sampling sites, strains of both mating types were present, indicating that compatible strains were in close proximity in the environment.

scholarly journals TEL/AML-1 dimerizes and is associated with a favorable outcome in childhood acute lymphoblastic leukemia

Blood ◽  
1996 ◽  
Vol 88 (11) ◽  
pp. 4252-4258 ◽  
Author(s):  
TW McLean ◽  
S Ringold ◽  
D Neuberg ◽  
K Stegmaier ◽  
R Tantravahi ◽  
...  
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Lymphoblastic Leukemia ◽  
Chromosomal Translocation ◽  
Fusion Transcript ◽  
Childhood Acute Lymphoblastic Leukemia ◽  
Childhood All ◽  
Polymerase Chain ◽  
B Lineage

Abstract Polymerase chain reaction-based screening of childhood acute lymphoblastic leukemia (ALL) samples showed that a TEL/AML1 fusion transcript was detected in 27% of all cases, representing the most common known gene rearrangement in childhood cancer. The TEL/AML1 fusion results from a t(12;21)(p13;q22) chromosomal translocation, but was undetectable at the routine cytogenetic level. TEL/AML1-positive patients had exclusively B-lineage ALL, and most patients were between the ages of 2 and 9 years at diagnosis. Only 3/89 (3.4%) adult ALL patients were TEL/AML1-positive. Most importantly, TEL/AML1-positive children had a significantly lower rate of relapse compared with TEL/AML1-negative patients (0/22 v 16/54, P = .004). Co- immunoprecipitation experiments demonstrated that TEL/AML-1 formed homodimers in vitro, and heterodimerized with the normal TEL protein when the two proteins were expressed together. The elucidation of the precise mechanism of transformation by TEL/AML1 and the role of TEL/AML1 testing in the treatment of childhood ALL will require additional studies.

scholarly journals Mating-Type Genes from Asexual Phytopathogenic Ascomycetes Fusarium oxysporum and Alternaria alternata

2000 ◽  
Vol 13 (12) ◽  
pp. 1330-1339 ◽  
Author(s):  
Tsutomu Arie ◽  
Isao Kaneko ◽  
Takanobu Yoshida ◽  
Masami Noguchi ◽  
Yoshikuni Nomura ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Mating Type ◽  
Alternaria Alternata ◽  
High Mobility ◽  
Hmg Box ◽  
Starting Point ◽  
Mating Type Genes ◽  
Polymerase Chain ◽  
Flanking Regions ◽  
Mat Genes

Mating-type (MAT) loci were cloned from two asexual (mitosporic) phytopathogenic ascomycetes, Fusarium oxysporum (a pyrenomycete) and Alternaria alternata (a loculoascomycete), by a polymerase chain reaction (PCR)-based strategy. The conserved high mobility group (HMG) box domain found in the MAT1-2-1 protein was used as a starting point for cloning and sequencing the entire MAT1-2 idiomorph plus flanking regions. Primer pairs designed to both flanking regions were used to amplify the opposite MAT1-1 idiomorph. The MAT1-1 and MAT1-2 idiomorphs were approximately 4.6 and 3.8 kb in F. oxysporum and approximately 1.9 and 2.2 kb in A. alternata, respectively. In both species, the MAT1-1 idiomorph contains at least one gene that encodes a protein with a putative alpha box domain and the MAT1-2 idiomorph contains one gene that encodes a protein with a putative HMG box domain. MAT-specific primers were used to assess the mating type of F. oxysporum and A. alternata field isolates by PCR. MAT genes from A. alternata were expressed. The A. alternata genes were confirmed to be functional in a close sexual relative, Cochliobolus heterostrophus, by heterologous expression.

Inhibition of hypoxia-inducible factor-1α by PX-478 as a potential targeted therapy in ESCC.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e14083-e14083
Author(s):  
Yingming Zhu ◽  
Yuanwei Zang ◽  
Minghuan Li ◽  
Jinming Yu
Keyword(s):  
Targeted Therapy ◽  
Hypoxia Inducible Factor ◽  
Radical Resection ◽  
Carcinoma Cells ◽  
Migration And Invasion ◽  
Hypoxia Inducible Factor 1Α ◽  
Polymerase Chain ◽  
Cox 2

e14083 Background: Hypoxia is a unique microenvironment in solid tumors, including ESCC. We aim to investigate the interaction between hypoxia-inducible factor-1α (HIF-1α), COX-2 and programmed cell death ligand-1 (PD-L1) and uncover the role of HIF-1α inhibitor PX-478 as a potential targeted therapy in ESCC. Methods: Immunohistochemical staining was performed to investigate the levels of HIF-1α, COX-2 and PD-L1 from 133 pT3N0M0 ESCC patients after radical resection. The prognostic value of the expression of HIF-1α, COX-2 and PD-L1 and the correlation with clinicopathologic features was evaluated. Knockdown assay, CCK-8 assay, Western blot, real-time polymerase chain reaction (RT-PCR), flow cytometry and Transwell migration assays were used in cells experiment. Results: HIF-1α and PD-L1 are independent prognostic factors in pT3N0M0 ESCC. Further data showed that HIF-1α plays an important role in regulation of COX-2 and PD-L1 expression. Our in vitro studies demonstrated that HIF-1α inhibitor, PX-478, induced G2 phase arrest, increased apoptosis, and inhibited migration and invasion of esophageal carcinoma cells, and thus significantly inhibit ESCC cells proliferation. Conclusions: Our results provide new insight into the potential role of HIF-1α inhibitors, PX-478 and open up the possibility of PX-478 for targeted therapy of ESCC.

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