The Gß-like protein Bcgbl1 regulates development and pathogenicity of the gray mold Botrytis cinerea via modulating two MAP kinase signaling pathways.

The fungal Gß-like protein has been reported to be involved in a variety of biological processes, such as mycelial growth, differentiation, conidiation, stress responses and infection. However, molecular mechanisms of the Gß-like protein in regulating fungal development and pathogenicity are largely unknown. Here, we show that the Gß-like protein gene Bcgbl1 in the gray mold fungus Botrytis cinerea plays a pivotal role in development and pathogenicity by regulating the mitogen-activated protein (MAP) kinases signaling pathways. The Bcgbl1 deletion mutants were defective in mycelial growth, sclerotial formation, conidiation, macroconidial morphogenesis, plant adhesion, and formation of infection cushions and appressorium-like structures, resulting in a complete loss of pathogenicity. Bcgbl1 interacted with BcSte50, the adapter protein of the cascade of MAP kinase (MAPK). Bcgbl1 mutants had reduced phosphorylation levels of two MAPKs, namely Bmp1 and Bmp3, thereby reducing infection. However, deletion of Bcgbl1 did not affect the intracellular cAMP level, and exogenous cAMP could not restore the defects. Moreover, Bcgbl1 mutants exhibited defects in cell wall integrity and oxidative stress tolerance. Transcriptional profiling revealed that Bcgbl1 plays a global role in regulation of gene expression upon hydrophobic surface induction. We further uncovered that three target genes encoding the hydrophobic surface binding proteins (HsbAs) contributed to the adhesion and virulence of B. cinerea. Overall, these findings suggest that Bcgbl1 had multiple functions and provided new insights for deciphering the Bcgbl1-mediated network for regulating development and pathogenicity of B. cinerea.

Characterization and phylogenetic analysis of the chloroplast genome of Solanum pseudocapsicum (Solanaceae).

Solanum pseudocapsicum Linnaeus 1753, a popular indoor potted plant known for its ornamental fruits, had its chloroplast genome sequenced in this study to determine its phylogenetic relationship with other related species and to construct a phylogenetic analysis tree. The research findings are as follows: 1. The chloroplast genome of S. pseudocapsicum comprises a large single-copy (LSC) region of 86,260 base pairs, a small single-copy (SSC) region of 18,325 base pairs, and two inverted repeat (IR) regions, each measuring 25,390 base pairs in length. 2. The G + C content of the entire chloroplast genome is 37.59%, with the highest G + C content found in the IR regions, reaching 43.03%; followed by the LSC region, which has a G + C content of 35.68%; and the lowest in the SSC region, with a G + C content of 31.53%. 3. The genome contains 127 genes, including 82 protein-coding genes, 37 tRNA genes, and 8 rRNA genes, with 18 genes duplicated in the IR regions. 4. Phylogenetic analysis revealed that S. pseudocapsicum, Solanum betaceum, Solanum laciniatum, and Solanum nitidum are genetically closely related and are located on the same branch of the phylogenetic tree, indicating a close relationship among them. This study provides a foundation for the identification, classification, and exploration of genetic diversity within the Solanum genus.