TITLE:
Identification and Expression of Some Plant Cell Wall-Degrading Enzymes Present in Three Ontogenetics Stages of Thecaphora frezii, a Peanut (Arachis hypogaea L.) Pathogenic Fungus
AUTHORS:
Néstor Walter Soria, Ana Cristina Figueroa, María Soledad Díaz, Valeria Roxana Alasino, Pablo Yang, Dante Miguel Beltramo
KEYWORDS:
Carbohydrate-Degrading Enzymes, Phytopathogenic Fungi, Smut Fungi, Transcriptome, Thecaphora frezii
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.13 No.1,
January
13,
2022
ABSTRACT: Peanuts can be affected by the presence of
pathogenic microorganisms. The fungus Thecaphora
frezii (T. frezii), which belongs
to the taxonomic class Ustilaginomycetes, is the causal agent of the disease
known as “peanut smut”. The life cycle of this fungus includes three stages,
namely teliospores, basidiospores and hyphae. In the hyphae stage, infection
occurs in the peanut plant, which requires the involvement of some enzymes
secreted by the fungus. These include the Plant Cell Wall-Degrading Enzymes
(PCWDEs), which degrade various polysaccharides. This study aimed to identify
the presence of transcript for enzymes belonging to the PCWDEs from three
stages of T. frezii. For this, total
RNA was extracted from the three ontogenetic stages of T. frezii. These samples were analyzed using an RNA-Seq approach
and some transcripts were quantified using Real Time PCR. The analysis of the
data provided by the RNA-Seq of the three T.
frezii stages, it was possible to identify some transcripts that could
encode enzymes compatible with polysaccharides degradation that are part of the
plant cell wall. In T. frezii transcriptome, 40 deduced proteins would be enzymes with functions of PCWDEs
were identified. They were divided into 27 glycoside hydrolases; two
polysaccharide lyases; three carbohydrate esterases and eight enzymes with
auxiliary activities. In addition, the fungal SNF1 gene was identified whose
activity could be affected by high glucose level, and indirectly influence the
levels of some PCWDEs. The analysis of the PCWDEs could help to understand part
of the fungal infection process and possibly find substances that can control
its development.