Single cell transcriptomics of neighboring hyphae of Aspergillus niger

Bekker, Charissa de; Bruning, Oskar; Jonker, Martijs J.; Breit, Timo M.; Wösten, Han A. B.

doi:10.1186/gb-2011-12-8-r71

Cited by 72 publications

(67 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the mechanism of septum reinforcement is likely to be complex and more work will be required to understand precisely how SPA-19 and HDA-2 protect the septum from degeneration. In Aspergillus niger, neighboring hyphae can present distinct gene expression profiles (de Bekker et al, 2011). As with data presented here, this conforms with the idea that the genetic identity of hyphal segments is not solely determined by age and environment.…”

Section: Discussionsupporting

confidence: 91%

Cellular Subcompartments through Cytoplasmic Streaming

et al. 2015

View full text Add to dashboard Cite

Cytoplasmic streaming occurs in diverse cell types, where it generally serves a transport function. Here, we examine streaming in multicellular fungal hyphae and identify an additional function wherein regimented streaming forms distinct cytoplasmic subcompartments. In the hypha, cytoplasm flows directionally from cell to cell through septal pores. Using live-cell imaging and computer simulations, we identify a flow pattern that produces vortices (eddies) on the upstream side of the septum. Nuclei can be immobilized in these microfluidic eddies, where they form multinucleate aggregates and accumulate foci of the HDA-2 histone deacetylase-associated factor, SPA-19. Pores experiencing flow degenerate in the absence of SPA-19, suggesting that eddy-trapped nuclei function to reinforce the septum. Together, our data show that eddies comprise a subcellular niche favoring nuclear differentiation and that subcompartments can be self-organized as a consequence of regimented cytoplasmic streaming.

show abstract

Section: Discussionsupporting

confidence: 91%

Cellular Subcompartments through Cytoplasmic Streaming

et al. 2015

View full text Add to dashboard Cite

show abstract

“…A unified mechanism could apply locally to all cell types, but it is also possible that differential expression could be limited to a particular subpopulation of cells. Although apical hyphae are often presumed responsible for the bulk of fungal protein secretion (30,31), expression patterns that are locally heterogeneous can arise due to nonuniform gene expression within the mycelium (32) and to protein secretion from subapical hyphal regions (33). Heterogeneous secretion of lignin peroxidases has, for example, been shown in the wood-degrading fungus Phanerochaete chrysosporium (34).…”

Section: Discussionmentioning

confidence: 99%

Localizing gene regulation reveals a staggered wood decay mechanism for the brown rot fungus Postia placenta

Zhang

Presley

Hammel

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

160

206

View full text Add to dashboard Cite

Wood-degrading brown rot fungi are essential recyclers of plant biomass in forest ecosystems. Their efficient cellulolytic systems, which have potential biotechnological applications, apparently depend on a combination of two mechanisms: lignocellulose oxidation (LOX) by reactive oxygen species (ROS) and polysaccharide hydrolysis by a limited set of glycoside hydrolases (GHs). Given that ROS are strongly oxidizing and nonselective, these two steps are likely segregated. A common hypothesis has been that brown rot fungi use a concentration gradient of chelated metal ions to confine ROS generation inside wood cell walls before enzymes can infiltrate. We examined an alternative: that LOX components involved in ROS production are differentially expressed by brown rot fungi ahead of GH components. We used spatial mapping to resolve a temporal sequence in Postia placenta, sectioning thin wood wafers colonized directionally. Among sections, we measured gene expression by whole-transcriptome shotgun sequencing (RNA-seq) and assayed relevant enzyme activities. We found a marked pattern of LOX up-regulation in a narrow (5-mm, 48-h) zone at the hyphal front, which included many genes likely involved in ROS generation. Up-regulation of GH5 endoglucanases and many other GHs clearly occurred later, behind the hyphal front, with the notable exceptions of two likely expansins and a GH28 pectinase. Our results support a staggered mechanism for brown rot that is controlled by differential expression rather than microenvironmental gradients. This mechanism likely results in an oxidative pretreatment of lignocellulose, possibly facilitated by expansin-and pectinase-assisted cell wall swelling, before cellulases and hemicellulases are deployed for polysaccharide depolymerization.B rown rot wood-degrading fungi release sequestered carbon from lignocellulose in forests (1) and have the unique ability to accomplish this without significantly removing the recalcitrant lignin that encases the structural polysaccharides. Accordingly, their decay mechanisms may provide a model for new biomass conversion technologies that not only function despite the presence of lignin but also yield lignin as a potentially useful coproduct (1-3). Deviating from their white rot ancestors, brown rot fungi have evolved mechanisms that are generally faster (4, 5) and more polysaccharide-specific because they circumvent lignin (4,(6)(7)(8). This enhanced efficiency is coupled with losses, not expansions, of key white rot genes, including many linked to lignin degradation and processive cellulose hydrolysis. For example, few brown rot fungi produce the cellobiohydrolases that are included in commercial synergistic glycoside hydrolase (GH) mixtures (9-12). These observations imply that brown rot fungi harbor novel pathways to improve saccharification yields.To explain why brown rot fungi are so efficient, despite their minimal toolkit of biodegradative enzymes, low-molecular-weight (LMW) oxidative agents have been proposed to operate in tandem with the enzymes. ...

show abstract

“…The PCR product was digested with NotI and NcoI and ligated with the 4 kb NotI/NcoI fragment of pCB034 (de Bekker et al 2011) harboring the H2B-GFP fusion sequence. This plasmid was named pRB009.…”

Section: Construction Of the Nuclear Gfp Expression Plasmidmentioning

confidence: 99%

VeA of Aspergillus niger increases spore dispersing capacity by impacting conidiophore architecture

Wang

Dijksterhuis

Wyatt

et al. 2014

Antonie van Leeuwenhoek

View full text Add to dashboard Cite

Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger maximizes the diameter of the vesicle and the spore chain length. The length and width of the conidiophore stalk and vesicle were reduced nearly twofold in a DveA strain. The latter implies a fourfold reduced surface area to develop chains of spores. Over and above this, the conidial chain length was approximately fivefold reduced. The calculated 20-fold reduction in formation of conidia by DveA fits the 8-to 17-fold decrease in counted spore numbers. Notably, morphology of the DveA conidiophores of A. niger was very similar to that of wild-type Aspergillus sydowii. This suggests that VeA is key in conidiophore architecture diversity in the fungal kingdom. The finding that biomass formation of the A. niger DveA strain was reduced twofold shows that VeA not only impacts dispersion capacity but also colonization capacity of A. niger.

show abstract

Single cell transcriptomics of neighboring hyphae of Aspergillus niger

Cited by 72 publications

References 34 publications

Cellular Subcompartments through Cytoplasmic Streaming

Cellular Subcompartments through Cytoplasmic Streaming

Localizing gene regulation reveals a staggered wood decay mechanism for the brown rot fungus Postia placenta

VeA of Aspergillus niger increases spore dispersing capacity by impacting conidiophore architecture

Contact Info

Product

Resources

About