Jahan, Sultana Nilufar
(2015).
Small RNAs in Phytophthora infestans and cross-talk with potato.
Diss. (sammanfattning/summary)
Uppsala :
Sveriges lantbruksuniv.,
Acta Universitatis Agriculturae Sueciae, 1652-6880
; 2015:113
ISBN 978-91-576-8424-0
eISBN 978-91-576-8425-7
[Doctoral thesis]
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Abstract
Small RNAs (sRNAs) are small non-coding RNAs usually ranging in size 20-30 nt. They are playing important roles in plant-pathogen interactions. This thesis aimed at studying the sRNA populations in potato and Phytophthora infestans and their role in the potato-P. infestans interaction. An attempt was also made to implement such knowledge to improve resistance in potato against P. infestans.
P. infestans is an oomycete that causes severe damage to potato and tomato, and is well known for its ability to evolve rapidly to overcome resistance. It possesses active RNA silencing pathways and sRNAs are playing important roles to control the large numbers of transposable elements (TE) present in its genome and effector genes. Through deep sequencing of sRNAs from two isolates of P. infestans differing in pathogenicity, three clear size classes (21, 25/26 and 32 nt) of sRNAs were identified. RxLR and Crinkler (CRN) effector gene-derived sRNAs were present in both isolates, but exhibited marked differences in abundance. Some effector genes, such as PiAvr3a and PiAvrblb2, to which sRNAs were found, also exhibited differences in transcript accumulation between the two isolates. Majority of sRNAs also mapped to TEs. An additional group of sRNAs, the tRNA-derived RNA fragments (tRFs) ranging in size from 19-40 nt was identified in P. infestansm as well. Some tRFs accumulated differentially during infection.
A host-induced gene-silencing (HIGS) approach was proven to be successful in the potato-P. infestans pathosystem. Four different endogenous genes in P. infestans were targeted in my study by HIGS constructs and choice of target gene was shown crucial for a successful outcome. HIGS has the potential to be adopted in new resistance breeding to improve resistance in potato against P. infestans.
One late blight resistant potato cultivar was sequenced upon infection with compatible isolate of P. infestans. In order to decipher the molecular events underlying its resistance breakdown, analysis of transcript change and the possible role of sRNAs on transcript regulation during infection are ongoing. In infected potato, resistance genes are targeted by its own miRNAs leading to suppression. Additional components are most likely involved in this process and near future analysis will help to enhance our understanding of how P. infestans uses sRNAs to evade plant immune responses.
Authors/Creators: | Jahan, Sultana Nilufar | ||||||||||
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Title: | Small RNAs in Phytophthora infestans and cross-talk with potato | ||||||||||
Series Name/Journal: | Acta Universitatis Agriculturae Sueciae | ||||||||||
Year of publishing : | December 2015 | ||||||||||
Depositing date: | 10 December 2015 | ||||||||||
Number: | 2015:113 | ||||||||||
Number of Pages: | 62 | ||||||||||
Papers/manuscripts: |
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Place of Publication: | Uppsala | ||||||||||
Publisher: | Department of Plant Biology, Swedish University of Agricultural Sciences | ||||||||||
ISBN for printed version: | 978-91-576-8424-0 | ||||||||||
ISBN for electronic version: | 978-91-576-8425-7 | ||||||||||
ISSN: | 1652-6880 | ||||||||||
Language: | English | ||||||||||
Publication Type: | Doctoral thesis | ||||||||||
Full Text Status: | Public | ||||||||||
Agris subject categories.: | F Plant production > F30 Plant genetics and breeding H Protection of plants and stored products > H20 Plant diseases | ||||||||||
Subjects: | (A) Swedish standard research categories 2011 > 4 Agricultural Sciences > 404 Agricultural Biotechnology > Plant Biotechnology | ||||||||||
Agrovoc terms: | solanum tuberosum, phytophthora infestans, oomycetes, pathogens, genes, rna, effectors, gene expression | ||||||||||
Keywords: | Phytophthora infesters, potato, sRNA, miRNA, HIGS, effector | ||||||||||
URN:NBN: | urn:nbn:se:slu:epsilon-e-3133 | ||||||||||
Permanent URL: | http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-e-3133 | ||||||||||
ID Code: | 12905 | ||||||||||
Faculty: | NJ - Fakulteten för naturresurser och jordbruksvetenskap | ||||||||||
Department: | (NL, NJ) > Department of Plant Biology (from 140101) | ||||||||||
External funders: | FORMAS and Jordbruksverket / Swedish Board of Agriculture and Stiftelsen Lantbruksforskning and Swedish Research Council | ||||||||||
Deposited By: | Sultana Nilufar Jahan | ||||||||||
Deposited On: | 11 Dec 2015 09:22 | ||||||||||
Metadata Last Modified: | 10 Sep 2020 13:41 |
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