Genome-Wide Identification, Phylogeny and Expression Profile of Vesicle Fusion Components in Verticillium dahliae

Abstract

Vesicular trafficking plays a crucial role in protein localization and movement, signal transduction, and multiple developmental processes in eukaryotic cells. Vesicle fusion is the final and key step in vesicle-mediated trafficking and mainly relies on SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors), the regulators including SM (Sec1/Munc18) family proteins, Rab GTPases and exocyst subunits. Verticillium dahliae is a widespread soil fungus that causes disruptive vascular diseases on a wide range of plants. To date, no genes involved in vesicular fusion process have been identified and characterized in V. dahliae. The recent publication of the draft genome sequence of V. dahliae allowed us to conduct a genome-wide identification, phylogeny and expression profile of genes encoding vesicular fusion components. Using compared genomics and phylogenetic methods, we identified 44 genes encoding vesicle fusion components in the V. dahliae genome. According to the structural features of their encoded proteins, the 44 V. dahliae genes were classified into 22 SNAREs (6 Qa-, 4 Qb-, 6 Qc-, 1 Qbc- and 5 R-types), 4 SM family proteins, 10 Rab GTPases and 8 exocyst proteins. Based on phylogeny and motif constitution analysis, orthologs of vesicle fusion component in filamentous fungi were generally clustered together into the same subclasses with well-supported bootstrap values. Analysis of the expression profiles of these genes indicated that many of them are significantly differentially expressed during vegetative growth and microsclerotia formation in V. dahliae. The analysis show that many components of vesicle fusion are well conserved in filamentous fungi and indicate that vesicle fusion plays a critical role in microsclerotia formation of smoke tree wilt fungus V. dahliae. The genome-wide identification and expression analysis of components involved in vesicle fusion should facilitate research in this gene family and give new insights toward elucidating their functions in growth, development and pathogenesis of V. dahliae.

Genomics Spurs Rapid Advances in Our Understanding of the Biology of Vascular Wilt Pathogens in the Genus Verticillium

“…Although light and electron microscopic examinations have defined the morphological sequence of events in the microsclerotial developmental pathway (see précis in Reference 70 and Figure 1), the molecular mechanisms that direct microsclerotial development remain for the most part uncharacterized. However, with genomics-based studies now coming to the fore, genes involved in this developmental process are coming to light through transcriptional profiling and genome-scale random mutagenesis (19,13,41,70,72).…”

A novel gene from a secondary metabolism gene cluster is required for microsclerotia formation and virulence in Verticillium dahliae

“…However, annotation of gene model predictions could potentially be improved using multiple methods performed in F. graminearum (Wong et al 2011;Zhao et al 2013). Our previous work also revised an erroneous annotation of gene model in V. dahliae based on sequence alignment and reverse-transcription PCR (Yang et al 2013).…”

Host‐induced gene silencing of a regulator of G protein signalling gene (VdRGS1) confers resistance to Verticillium wilt in cotton

“…VdMsb encodes a transmembrane mucin that is highly conserved in the MAPK signal pathway and plays a role in development and virulence in V. dahliae (Tian et al, 2014). Moreover, those homologous genes that are thought to play roles in G protein signalling, including cAMP-dependent PKA pathway signalling (Tzima et al, 2010), and vesicle fusion (Yang et al, 2013). Among these components, VdPKAC1, the catalytic subunit of cAMP-dependent PKA, regulates the microsclerotia production, indicating that the cAMP pathway antagonizes the VMK1 kinasemediated pathway in the regulation of microsclerotia formation (Tzima et al, 2010).…”