Host Species-Specific Protoplast Damaging Activity of Spore Germination Fluids of Blast Pathogen Magnaporthe grisea

2002 ◽  
Vol 150 (10) ◽  
pp. 576-578 ◽  
Author(s):  
R. Rathour ◽  
B. M. Singh ◽  
P. Plaha
Genome ◽  
2006 ◽  
Vol 49 (8) ◽  
pp. 873-881 ◽  
Author(s):  
Q H Chen ◽  
Y C Wang ◽  
X B Zheng

We analyzed host-species specificity of Magnaporthe grisea on rice using 110 F1 progeny derived from a cross between the Oryza isolate CH87 (pathogenic to rice) and the Digitaria isolate 6023 (pathogenic to crabgrass). To elucidate the genetic mechanisms controlling species specificity in M. grisea, we performed a genetic analysis of species-specific avirulence on this rice population. Avirulent and virulent progeny segregated in a 1:1 ratio on the 2 rice cultivars 'Lijiangxintuanheigu' (LTH) and 'Shin2', suggesting that a single locus, designated PRE1, was involved in the specificity. In a combination between 'Kusabue' and 'Tsuyuake', the segregation of the 4 possible phenotypes of F1 progeny was significantly different from the expected 3:1:3:1 and instead fit a ratio of 2:0:1:1. This indicated that 2 loci, PRE1 and AVR2, were involved in specific parasitism on rice. These results suggest that the species specificity of M. grisea on rice is governed by species-dependent genetic mechanisms that are similar to the gene-for-gene interactions controlling cultivar specificity. Pathogenicity tests with various plant species revealed that the Digitaria isolate 6023 was exclusively parasitic on crabgrass. Genetic linkage analysis showed that PRE1 was mapped on chromosome 3 with respect to RAPD and SSR markers. RAPD marker S361 was linked to the avirulence gene at a distance of ~6.4 cM. Two SSR markers, m677–678 and m77–78, were linked to the PRE1 gene on M. grisea chromosome 3 at distances of 5.9 and 7.1 cM, respectively. Our results will facilitate positional cloning and functional studies of this gene.Key words: genetic analysis, graminaceous plants, Magnaporthe grisea, species-specific avirulence gene.


2021 ◽  
Author(s):  
Jennifer L. Houtz ◽  
Jon G. Sanders ◽  
Anthony Denice ◽  
Andrew H. Moeller

2020 ◽  
Vol 375 (1808) ◽  
pp. 20190598 ◽  
Author(s):  
Laura Grieneisen ◽  
Amanda L. Muehlbauer ◽  
Ran Blekhman

Recent comparative studies have found evidence consistent with the action of natural selection on gene regulation across primate species. Other recent work has shown that the microbiome can regulate host gene expression in a wide range of relevant tissues, leading to downstream effects on immunity, metabolism and other biological systems in the host. In primates, even closely related host species can have large differences in microbiome composition. One potential consequence of these differences is that host species-specific microbial traits could lead to differences in gene expression that influence primate physiology and adaptation to local environments. Here, we will discuss and integrate recent findings from primate comparative genomics and microbiome research, and explore the notion that the microbiome can influence host evolutionary dynamics by affecting gene regulation across primate host species. This article is part of the theme issue ‘The role of the microbiome in host evolution’.


2008 ◽  
Vol 14 (4) ◽  
pp. 223-231 ◽  
Author(s):  
Regina Lizundia ◽  
Kay-Sara Sauter ◽  
Geraldine Taylor ◽  
Dirk Werling

1987 ◽  
Vol 21 (6) ◽  
pp. 589-595 ◽  
Author(s):  
Jeffrey M. Bockman ◽  
Stanley B. Prusiner ◽  
Jun Tateishi ◽  
David T. Kingsbury

2002 ◽  
Vol 92 (11) ◽  
pp. 1182-1188 ◽  
Author(s):  
N. Takabayashi ◽  
Y. Tosa ◽  
H. S. Oh ◽  
S. Mayama

To elucidate genetic mechanisms of the species-specific parasitism of Magnaporthe grisea, a Triticum isolate (pathogenic on wheat) was crossed with an Avena isolate (pathogenic on oat), and resulting F1 progeny were subjected to segregation analyses on wheat cvs. Norin 4 and Chinese Spring. We found two fungal loci, Pwt3 and Pwt4, which are involved in the specific parasitism on wheat. Pwt3 operated on both cultivars while Pwt4 operated only on ‘Norin 4’. Using the cultivar specificity of Pwt4, its corresponding resistance gene was successfully identified in ‘Norin 4’ and designated as Rmg1 (Rwt4). The presence of the corresponding resistance gene indicated that Pwt4 is an avirulence locus. Pwt3 was assumed to be an avirulence locus because of its temperature sensitivity. We suggest that gene-for-gene interactions underlie the species-specific parasitism of M. grisea.


2020 ◽  
Author(s):  
Connie A. Rojas ◽  
Santiago A. Ramírez-Barahona ◽  
Kay E. Holekamp ◽  
Kevin. R. Theis

AbstractThe gut microbiota is critical for host function. Among mammals, host phylogenetic relatedness and diet are strong drivers of gut microbiota structure, but one factor may be more influential than the other. Here, we used 16S rRNA gene sequencing to determine the relative contributions of host phylogeny and host dietary guild in structuring the gut microbiotas of 11 herbivore species from 5 families living sympatrically in southwest Kenya. Herbivore species were classified as grazers, browsers, or mixed-feeders. We found that gut microbiotas were highly species-specific, and that host family accounted for more variation in the gut microbiota (35%) than did host dietary guild (14%). Overall, similarity among gut microbiotas increased with host phylogenetic relatedness (r=0.73), yet this relationship was not apparent among seven closely related Bovid host species (r=0.21 NS). In bovids, host dietary guild explained twice as much variation in the gut microbiota as did host species. Lastly, we found that the gut microbiotas of herbivores residing in southwest Kenya closely resemble those of conspecifics from central Kenya, suggesting that regardless of variability in host local habitat, hosts consistently provide microbes with similar niches for colonization. Overall, our findings suggest that host phylogeny may structure the gut microbiota at broad taxonomic scales, but that host ecology may be more influential in shaping the gut microbiotas of closely related host species.


Author(s):  
Jennifer Houtz ◽  
Jon Sanders ◽  
Anthony Denice ◽  
Andrew Moeller

Humans and non-human primates (NHPs) harbor complex gut microbial communities that affect phenotypes and fitness. The gut microbiotas of wild NHPs reflect their hosts’ phylogenetic histories and are compositionally distinct from those of humans, but in captivity the endogenous gut microbial lineages of NHPs can be lost or replaced by lineages found in humans. Despite its potential contributions to gastrointestinal dysfunction, this humanization of the gut microbiota has not been investigated systematically across captive NHP species. Here we show through comparisons of well-sampled wild and captive populations of apes and monkeys that the fraction of the gut microbiota humanized by captivity varies significantly between NHP species but is remarkably reproducible between captive populations of the same NHP species. Conspecific captive populations displayed significantly greater than expected overlap in the sets of bacterial 16S rRNA gene variants that were differentially abundant between captivity and the wild. This overlap was evident even between captive populations residing on different continents but was never observed between heterospecific captive populations. In addition, we developed an approach incorporating human gut microbiota data to rank NHPs’ gut microbial clades based on the propensity of their lineages to be lost or replaced by lineages found in humans in captivity. Relatively few microbial genera displayed reproducible degrees of humanization in different captive host species, but most microbial genera were reproducibly humanized or retained from the wild in conspecific pairs of captive populations. These results demonstrate that the gut microbiotas of captive NHPs display predictable, host-species specific responses to captivity.


2002 ◽  
Vol 80 (10) ◽  
pp. 1088-1095 ◽  
Author(s):  
H S Oh ◽  
Y Tosa ◽  
N Takabayashi ◽  
S Nakagawa ◽  
R Tomita ◽  
...  

An isolate of Magnaporthe grisea was collected from a blast lesion on oat in Brazil. Sequence analysis of the rDNA-ITS-2 region and DNA fingerprinting with repetitive elements revealed that the Avena isolate belongs to the "crop isolate group" and is similar to Triticum isolates. At high temperature (28°C), the Avena isolate caused severe disease symptoms on primary leaves of oat and wheat. When the temperature was decreased to 20°C, wheat leaves expressed resistance to the Avena isolate. Cytologically, this temperature-dependent resistance was associated with an increase in the incidences of papilla formation and a hypersensitive reaction. Pathogenicity tests with various plant species at 20°C revealed that the Avena isolate is exclusively parasitic on oat. To elucidate genetic mechanisms of this species-specific parasitism, the Avena isolate was crossed with a Triticum isolate and resulting F1 progenies were subjected to pathogenicity tests on oat seedlings. In the F1 population, avirulent and virulent cultures segregated in a 1:1 ratio, suggesting that the specific parasitism on oat is controlled by a single gene. This locus was designated as Pat1.Key words: Magnaporthe grisea, species-specific parasitism, oat, temperature sensitive.


Sign in / Sign up

Export Citation Format

Share Document