MyMedR

Displaying publications 21 - 25 of 25 in total

Abstract:

Sort:

Fulltext Analysis of the leaf transcriptome of Musa acuminata during interaction with Mycosphaerella musicola: gene assembly, annotation and marker development

Passos MA, de Cruz VO, Emediato FL, de Teixeira CC, Azevedo VC, Brasileiro AC, et al.

BMC Genomics, 2013 Feb 05;14:78.
PMID: 23379821 DOI: 10.1186/1471-2164-14-78

BACKGROUND: Although banana (Musa sp.) is an important edible crop, contributing towards poverty alleviation and food security, limited transcriptome datasets are available for use in accelerated molecular-based breeding in this genus. 454 GS-FLX Titanium technology was employed to determine the sequence of gene transcripts in genotypes of Musa acuminata ssp. burmannicoides Calcutta 4 and M. acuminata subgroup Cavendish cv. Grande Naine, contrasting in resistance to the fungal pathogen Mycosphaerella musicola, causal organism of Sigatoka leaf spot disease. To enrich for transcripts under biotic stress responses, full length-enriched cDNA libraries were prepared from whole plant leaf materials, both uninfected and artificially challenged with pathogen conidiospores.
RESULTS: The study generated 846,762 high quality sequence reads, with an average length of 334 bp and totalling 283 Mbp. De novo assembly generated 36,384 and 35,269 unigene sequences for M. acuminata Calcutta 4 and Cavendish Grande Naine, respectively. A total of 64.4% of the unigenes were annotated through Basic Local Alignment Search Tool (BLAST) similarity analyses against public databases.Assembled sequences were functionally mapped to Gene Ontology (GO) terms, with unigene functions covering a diverse range of molecular functions, biological processes and cellular components. Genes from a number of defense-related pathways were observed in transcripts from each cDNA library. Over 99% of contig unigenes mapped to exon regions in the reference M. acuminata DH Pahang whole genome sequence. A total of 4068 genic-SSR loci were identified in Calcutta 4 and 4095 in Cavendish Grande Naine. A subset of 95 potential defense-related gene-derived simple sequence repeat (SSR) loci were validated for specific amplification and polymorphism across M. acuminata accessions. Fourteen loci were polymorphic, with alleles per polymorphic locus ranging from 3 to 8 and polymorphism information content ranging from 0.34 to 0.82.
CONCLUSIONS: A large set of unigenes were characterized in this study for both M. acuminata Calcutta 4 and Cavendish Grande Naine, increasing the number of public domain Musa ESTs. This transcriptome is an invaluable resource for furthering our understanding of biological processes elicited during biotic stresses in Musa. Gene-based markers will facilitate molecular breeding strategies, forming the basis of genetic linkage mapping and analysis of quantitative trait loci.

Matched MeSH terms: Ascomycota/genetics
Fulltext Fatty Acid Synthase Beta Dehydratase in the Lipid Biosynthesis Pathway Is Required for Conidiogenesis, Pigmentation and Appressorium Formation in Magnaporthe oryzae S6

Sangappillai V, Nadarajah K

Int J Mol Sci, 2020 Sep 30;21(19).
PMID: 33007862 DOI: 10.3390/ijms21197224

Lipid biosynthesis produces glycerol, which is important in fueling turgor pressure necessary for germination and penetration of plant host by fungi. As the relationship between pathogenicity and the lipid biosynthetic pathway is not fully understood, we have elucidated the role of the fatty acid synthase beta subunit dehydratase (FAS1) gene in lipid biosynthesis. The FAS1 gene was silenced through homologous double crossover in Magnaporthe oryzae strain S6 to study the effect on lipid biosynthesis. The vegetative growth of Δfas1 mutants show the highest drop on oleic acid (between 10 and 50%), while the mycelial dry weight of mutants dropped significantly on all media. Conidiation of FAS1 mutants show a ~10- and ~5-fold reduction on oatmeal and Potato Dextrose Agar (PDA), respectively. Mutants formed mycelium that were mildly pigmented, indicating that the deletion of FAS1 may have affected melanin biosynthesis. Biochemical and gene expression studies concluded that the fatty acid degradation pathway might have been interrupted by FAS1 deletion. FAS1 mutants showed no enzyme activity on glucose or olive oil, suggesting that the mutants may lack functional peroxisomes and be defective in β-oxidation of fatty acids, hence explaining the reduced lipid deposits in the spores.

Matched MeSH terms: Ascomycota/genetics*
Molecular diversity of fungal endophytes isolated from Garcinia mangostana and Garcinia parvifolia

Sim JH, Khoo CH, Lee LH, Cheah YK

J Microbiol Biotechnol, 2010 Apr;20(4):651-8.
PMID: 20467234

Garcinia is commonly found in Malaysia, but limited information is available regarding endophytic fungi associated with this plant. In this study, 24 endophytic fungi were successfully recovered from different parts of two Garcinia species. Characterization of endophytic fungi was performed based on the conserved internal transcribed spacer (ITS) region sequence analysis and the antimicrobial properties. Results revealed that fruits of the plant appeared to be the highest inhabitation site (38 %) as compared with others. Glomerella sp., Guignardia sp., and Phomopsis sp. appeared to be the predominant endophytic fungi group in Garcinia mangostana and Garcinia parvifolia. Phylogenetic relationships of the isolated endophytic fungi were estimated from the sequences of the ITS region. On the other hand, antibacterial screening showed 11 of the isolates possessed positive response towards pathogenic and nonpathogenic bacteria. However, there was no direct association between certain antibacterial properties with the specific genus observed.

Matched MeSH terms: Ascomycota/genetics*
Fulltext Genome Anatomy of Pyrenochaeta unguis-hominis UM 256, a Multidrug Resistant Strain Isolated from Skin Scraping

Toh YF, Yew SM, Chan CL, Na SL, Lee KW, Hoh CC, et al.

PLoS One, 2016;11(9):e0162095.
PMID: 27626635 DOI: 10.1371/journal.pone.0162095

Pyrenochaeta unguis-hominis is a rare human pathogen that causes infection in human skin and nail. P. unguis-hominis has received little attention, and thus, the basic biology and pathogenicity of this fungus is not fully understood. In this study, we performed in-depth analysis of the P. unguis-hominis UM 256 genome that was isolated from the skin scraping of a dermatitis patient. The isolate was identified to species level using a comprehensive multilocus phylogenetic analysis of the genus Pyrenochaeta. The assembled UM 256 genome has a size of 35.5 Mb and encodes 12,545 putative genes, and 0.34% of the assembled genome is predicted transposable elements. Its genomic features propose that the fungus is a heterothallic fungus that encodes a wide array of plant cell wall degrading enzymes, peptidases, and secondary metabolite biosynthetic enzymes. Antifungal drug resistance genes including MDR, CDR, and ERG11/CYP51 were identified in P. unguis-hominis UM 256, which may confer resistance to this fungus. The genome analysis of P. unguis-hominis provides an insight into molecular and genetic basis of the fungal lifestyles, understanding the unrevealed biology of antifungal resistance in this fungus.

Matched MeSH terms: Ascomycota/genetics*
Fulltext The genome of newly classified Ochroconis mirabilis: Insights into fungal adaptation to different living conditions

Yew SM, Chan CL, Kuan CS, Toh YF, Ngeow YF, Na SL, et al.

BMC Genomics, 2016 Feb 03;17:91.
PMID: 26842951 DOI: 10.1186/s12864-016-2409-8

Ochroconis mirabilis, a recently introduced water-borne dematiaceous fungus, is occasionally isolated from human skin lesions and nails. We identified an isolate of O. mirabilis from a skin scraping with morphological and molecular studies. Its genome was then sequenced and analysed for genetic features related to classification and biological characteristics.

Matched MeSH terms: Ascomycota/genetics*