Vel2 and Vos1 hold essential roles in ascospore and asexual spore development of the heterothallic maize pathogen Cochliobolus heterostrophus

2014 ◽  
Vol 70 ◽  
pp. 113-124 ◽  
Author(s):  
Weiwei Wang ◽  
Dongliang Wu ◽  
Hongyu Pan ◽  
B. Gillian Turgeon
Keyword(s):  
Cochliobolus Heterostrophus ◽  
Spore Development ◽  
Asexual Spore

scholarly journals Sporogenic Effect of Polyunsaturated Fatty Acids on Development of Aspergillus spp

1999 ◽  
Vol 65 (8) ◽  
pp. 3668-3673 ◽  
Author(s):  
Ana M. Calvo ◽  
Lori L. Hinze ◽  
Harold W. Gardner ◽  
Nancy P. Keller
Keyword(s):  
Fatty Acids ◽  
Linoleic Acid ◽  
Aspergillus Parasiticus ◽  
Spore Production ◽  
Fungal Colonization ◽  
Fungal Development ◽  
Spore Development ◽  
Environmental Signals ◽  
Asexual Spore ◽  
Sclerotium Production

ABSTRACT Aspergillus spp. are frequently occurring seed-colonizing fungi that complete their disease cycles through the development of asexual spores, which function as inocula, and through the formation of cleistothecia and sclerotia. We found that development of all three of these structures in Aspergillus nidulans,Aspergillus flavus, and Aspergillus parasiticusis affected by linoleic acid and light. The specific morphological effects of linoleic acid include induction of precocious and increased asexual spore development in A. flavus and A. parasiticus strains and altered sclerotium production in someA. flavus strains in which sclerotium production decreases in the light but increases in the dark. In A. nidulans, both asexual spore production and sexual spore production were altered by linoleic acid. Spore development was induced in all three species by hydroperoxylinoleic acids, which are linoleic acid derivatives that are produced during fungal colonization of seeds. The sporogenic effects of these linoleic compounds on A. nidulans are similar to the sporogenic effects of A. nidulans psi factor, an endogenous mixture of hydroxylinoleic acid moieties. Light treatments also significantly increased asexual spore production in all three species. The sporogenic effects of light, linoleic acid, and linoleic acid derivatives on A. nidulans required an intactveA gene. The sporogenic effects of light and linoleic acid on Aspergillus spp., as well as members of other fungal genera, suggest that these factors may be significant environmental signals for fungal development.

scholarly journals Histidine Kinase Two-Component Response Regulator Proteins Regulate Reproductive Development, Virulence, and Stress Responses of the Fungal Cereal Pathogens Cochliobolus heterostrophus and Gibberella zeae

2010 ◽  
Vol 9 (12) ◽  
pp. 1867-1880 ◽  
Author(s):  
Shinichi Oide ◽  
Jinyuan Liu ◽  
Sung-Hwan Yun ◽  
Dongliang Wu ◽  
Alex Michev ◽  
...  
Keyword(s):  
Stress Responses ◽  
Histidine Kinase ◽  
Response Regulator ◽  
Gibberella Zeae ◽  
Cochliobolus Heterostrophus ◽  
Wild Type ◽  
Content Type ◽  
Major Mechanism ◽  
Asexual Spore ◽  
Mutant Phenotypes

ABSTRACT Histidine kinase (HK) phosphorelay signaling is a major mechanism by which fungi sense their environment. The maize pathogen Cochliobolus heterostrophus has 21 HK genes, 4 candidate response regulator (RR) genes (SSK1, SKN7, RIM15, REC1), and 1 gene (HPT1) encoding a histidine phosphotransfer domain protein. Because most HKs are expected to signal through RRs, these were chosen for deletion. Except for pigment and slight growth alterations for rim15 mutants, no measurable altered phenotypes were detected in rim15 or rec1 mutants. Ssk1p is required for virulence and affects fertility and proper timing of sexual development of heterothallic C. heterostrophus. Pseudothecia from crosses involving ssk1 mutants ooze masses of single ascospores, and tetrads cannot be found. Wild-type pseudothecia do not ooze. Ssk1p represses asexual spore proliferation during the sexual phase, and lack of it dampens asexual spore proliferation during vegetative growth, compared to that of the wild type. ssk1 mutants are heavily pigmented. Mutants lacking Skn7p do not display any of the above phenotypes; however, both ssk1 and skn7 mutants are hypersensitive to oxidative and osmotic stresses and ssk1 skn7 mutants are more exaggerated in their spore-type balance phenotype and more sensitive to stress than single mutants. ssk1 mutant phenotypes largely overlap hog1 mutant phenotypes, and in both types of mutant, the Hog1 target gene, MST1, is not induced. ssk1 and hog1 mutants were examined in the homothallic cereal pathogen Gibberella zeae, and pathogenic and reproductive phases of development regulated by Ssk1 and Hog1 were found to mirror, but also vary from, those of C. heterostrophus.

scholarly journals Genetic analysis of SecA–SecY interaction required for spore development inBacillus subtilis

2000 ◽  
Vol 184 (2) ◽  
pp. 285-289
Author(s):  
Hitomi Kobayashi ◽  
Yoshiaki Ohashi ◽  
Hideaki Nanamiya ◽  
Kei Asai ◽  
Fujio Kawamura
Keyword(s):  
Genetic Analysis ◽  
Spore Development

scholarly journals G-Protein β Subunit of Cochliobolus heterostrophus Involved in Virulence, Asexual and Sexual Reproductive Ability, and Morphogenesis

2004 ◽  
Vol 3 (6) ◽  
pp. 1653-1663 ◽  
Author(s):  
Sherif Ganem ◽  
Shun-Wen Lu ◽  
Bee-Na Lee ◽  
David Yu-Te Chou ◽  
Ruthi Hadar ◽  
...  
Keyword(s):  
Map Kinase ◽  
G Protein ◽  
Signal Transduction Pathway ◽  
Cochliobolus Heterostrophus ◽  
Wild Type ◽  
Heterotrimeric G Protein ◽  
Reproductive Ability ◽  
Pathway Gene ◽  
Mitogen Activated Protein ◽  
Nuclear Degradation

ABSTRACT Previous work established that mutations in mitogen-activated protein (MAP) kinase (CHK1) and heterotrimeric G-protein α (Gα) subunit (CGA1) genes affect the development of several stages of the life cycle of the maize pathogen Cochliobolus heterostrophus. The effects of mutating a third signal transduction pathway gene, CGB1, encoding the Gβ subunit, are reported here. CGB1 is the sole Gβ subunit-encoding gene in the genome of this organism. cgb1 mutants are nearly wild type in vegetative growth rate; however, Cgb1 is required for appressorium formation, female fertility, conidiation, regulation of hyphal pigmentation, and wild-type virulence on maize. Young hyphae of cgb1 mutants grow in a straight path, in contrast to those of the wild type, which grow in a wavy pattern. Some of the phenotypes conferred by mutations in CGA1 are found in cgb1 mutants, suggesting that Cgb1 functions in a heterotrimeric G protein; however, there are also differences. In contrast to the deletion of CGA1, the loss of CGB1 is not lethal for ascospores, evidence that there is a Gβ subunit-independent signaling role for Cga1 in mating. Furthermore, not all of the phenotypes conferred by mutations in the MAP kinase CHK1 gene are found in cgb1 mutants, implying that the Gβ heterodimer is not the only conduit for signals to the MAP kinase CHK1 module. The additional phenotypes of cgb1 mutants, including severe loss of virulence on maize and of the ability to produce conidia, are consistent with CGB1 being unique in the genome. Fluorescent DNA staining showed that there is often nuclear degradation in mature hyphae of cgb1 mutants, while comparable wild-type cells have intact nuclei. These data may be genetic evidence for a novel cell death-related function of the Gβ subunit in filamentous fungi.

Cochliobolus heterostrophus. [Distribution map].

2003 ◽  
Author(s):  
Keyword(s):  
South Carolina ◽  
New Caledonia ◽  
French Polynesia ◽  
American Samoa ◽  
Peninsular Malaysia ◽  
Marshall Islands ◽  
Cochliobolus Heterostrophus ◽  
Distribution Map ◽  
Mato Grosso ◽  
Brunei Darussalam

Abstract A new distribution map is provided for Cochliobolus heterostrophus (Drechsler) Drechsler Fungi: Ascomycota: Pleosporales Hosts: Maize (Zea mays), also a range of other crops, mostly legumes and cereals. Information is given on the geographical distribution in EUROPE, Bulgaria, Croatia, Cyprus, Denmark, France, Germany, Italy, Portugal, Romania, Russia, Southern, Russia, Spain, Switzerland, Ukraine, Yugoslavia (former), ASIA, Bangladesh, Bhutan, Brunei Darussalam, Cambodia, China, Anhui, Fujian, Gansu, Guangdong, Guangxi, Hebei, Heilongjiang, Henan, Hong Kong, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei, Menggu, Shaanxi, Shandong, Sichuan, Yunnan, Zhejiang, Christmas, Island, India, Andhra Pradesh, Assam, Bihar, Delhi, Haryana, Himachal Pradesh, Karnataka, Kerala, Lakshadweep, Madhya Pradesh, Meghalaya, Orissa, Punjab, Rajasthan, Uttar Pradesh, West Bengal, Indonesia, Irian Jaya, Java, Iran, Israel, Japan, Honshu, Kyushu, Shikoku, North Korea, Korea Republic, Laos, Malaysia, Peninsular Malaysia, Sabah, Sarawak, Myanmar, Nepal, Oman, Pakistan, Philippines, Sri Lanka, Taiwan, Thailand, Vietnam, AFRICA, Benin, Burkina Faso, Cameroon, Congo Democratic Republic, Cote d'Ivoire Egypt, Gabon, Ghana, Guinea, Kenya, Madagascar, Malawi, Mauritius, Mozambique, Niger, Nigeria, Reunion, Senegal, Sierra Leone, South Africa, Sudan, Swaziland, Tanzania, Togo, Zambia, Zimbabwe, NORTH AMERICA, Canada, New Brunswick, Nova Scotia, Ontario, Quebec, Mexico, USA, Arkansas, Delaware, District of Columbia, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Kentucky, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, New York, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Texas, West Virginia, CENTRAL AMERICA & CARIBBEAN, Bahamas, Belize, Cuba, El Salvador, Guadeloupe, Guatemala, Jamaica, Nicaragua, Panama, Puerto Rico, Trinidad and Tobago, SOUTH AMERICA, Argentina, Bolivia, Brazil, Bahia, Mato, Grosso, do Sul, Parana, Colombia, Ecuador, French, Guiana, Guyana, Paraguay, Suriname, Venezuela, OCEANIA, American, Samoa, Australia, New South Wales, Northern Territory, Queensland, Fiji, French, Polynesia, Guam, Marshall, islands, New Caledonia, New Zealand, Niue, Papua New Guinea, Samoa, Solomon, Islands, Tonga, Vanuatu.

Cochliobolus heterostrophus. [Distribution map].

1981 ◽  
Author(s):  
Keyword(s):  
New Caledonia ◽  
New South ◽  
Solomon Islands ◽  
American Samoa ◽  
Cochliobolus Heterostrophus ◽  
Distribution Map ◽  
Irian Jaya ◽  
South Wales ◽  
Western Samoa ◽  
New Hebrides

Abstract A new distribution map is provided for Cochliobolus heterostrophus (Drechsl.) Drechsl. Hosts: Maize (Zea mays) and other Gramineae. Information is given on the geographical distribution in AFRICA, Dahomey, Egypt, Ghana, Guinea, Ivory Coast, Kenya, Malawi, Mauritius, Niger, Nigeria, Reunion, Senegal, Sierra Leone, South Africa, Sudan, Swaziland, Togo, Zaire, Zambia, Zimbabwe, ASIA, Bangladesh, Brunei, Burma, Cambodia, China (Honan, Manchuria, Nanking, Yunnan), Hong Kong, India (Delhi, Himalayas & S. India, West Bengal), (Bihar, Punjab), (Laccadive Ils), Indonesia (Irian Jaya), (Java), Israel, Japan, Korea, Laos, Malaysia, (W) (Sabah), (Sarawak), Nepal, Pakistan (SW), Philippines, Western Samoa, Thailand, Vietnam, AUSTRALASIA & OCEANIA, Australia (New South Wales, NT, Qd), Fiji, Hawaii, New Caledonia, New Hebrides, New Zealand, Papua New Guinea, Western Samoa, American Samoa, Solomon Islands, EUROPE, Cyprus, Denmark, France, Germany, Italy, Portugal, Romania, Spain, Switzerland, USSR (Caucasus), Yugoslavia, NORTH AMERICA, Canada (Ontario), (Quebec), Mexico, USA (Pa to Fla and Tex.), CENTRAL AMERICA & WEST INDIES, Bahamas, Belize, Cuba, Guatemala, Jamaica, Nicaragua, Panama, Salvador, Trinidad, SOUTH AMERICA, Argentina (Tucuman), Bolivia, Brazil (Bahia), Colombia, Eucador, French, Guiana, Guyana, Paraguay, Surinam, Venezuela.

Dynamic localization of penicillin-binding proteins during spore development in Bacillus subtilis

Microbiology ◽  
2005 ◽  
Vol 151 (3) ◽  
pp. 999-1012 ◽  
Author(s):  
Dirk-Jan Scheffers
Keyword(s):  
Bacillus Subtilis ◽  
Green Fluorescent Protein ◽  
Binding Proteins ◽  
Cytoplasmic Membrane ◽  
Fluorescent Protein ◽  
Spore Formation ◽  
The Other ◽  
Spore Development ◽  
Penicillin Binding Proteins ◽  
Green Fluorescent

During Bacillus subtilis spore formation, many membrane proteins that function in spore development localize to the prespore septum and, subsequently, to the outer prespore membrane. Recently, it was shown that the cell-division-specific penicillin-binding proteins (PBPs) 1 and 2b localize to the asymmetric prespore septum. Here, the author studied the localization of other PBPs, fused to green fluorescent protein (GFP), during spore formation. Fusions to PBPs 4, 2c, 2d, 2a, 3, H, 4b, 5, 4a, 4* and X were expressed during vegetative growth, and their localization was monitored during sporulation. Of these PBPs, 2c, 2d, 4b and 4* have been implicated as having a function in sporulation. It was found that PBP2c, 2d and X changed their localization, while the other PBPs tested were not affected. The putative endopeptidase PbpX appears to spiral out in a pattern that resembles FtsZ redistribution during sporulation, but a pbpX knockout strain had no distinguishable phenotype. PBP2c and 2d localize to the prespore septum and follow the membrane during engulfment, and so are redistributed to the prespore membrane. A similar pattern was observed when GFP–PBP2c was expressed in the mother cell from a sporulation-specific promoter. This work shows that various PBPs known to function during sporulation are redistributed from the cytoplasmic membrane to the prespore.

Ascospore abortion in crosses of Cochliobolus heterostrophus heterozygous for the virulence locus Tox1

Genome ◽  
1988 ◽  
Vol 30 (1) ◽  
pp. 12-18 ◽  
Author(s):  
Charlotte R. Bronson
Keyword(s):  
Key Words ◽  
Reciprocal Translocation ◽  
High Frequency ◽  
Chromosome Rearrangement ◽  
Cochliobolus Heterostrophus ◽  
Bipolaris Maydis ◽  
Field Isolates

Crosses heterozygous for the virulence locus Tox1 show a high frequency of nonrandom ascospore abortion, in addition to a high frequency of random abortion seen in homozygous crosses. In crosses among closely related laboratory strains, the frequency of asci with eight mature, viable spores dropped from 35–47% of asci with mature spores in crosses homozygous for Tox1 to 3–17% in heterozygous crosses. Segregation for alternate alleles of Tox1 was 2:2 in 98% of asci with four viable spores. Patterns of abortion in crosses involving field isolates were similar to the patterns in crosses among laboratory strains. No recombinants between Tox1 and the abortion-inducing factor were detected among 112 progeny of laboratory strains. The results suggest that race T (TOX1) and race O (tox1) strains of C. heterostrophus differ by a chromosome rearrangement, possibly a reciprocal translocation, with a breakpoint at or near Tox1.Key words: fertility, T-toxin, Cochliobolus heterostrophus, Helminthosporium maydis, Bipolaris maydis, Drechslera maydis, chromosome rearrangement, reciprocal translocation.

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