Four New Species and One New Record of Thelephora from China.

Species of the genus Thelephora (Thelephorales, Thelephoraceae) are ectomycorrhizal symbionts of coniferous and broad-leaved plants, and some of them are well-known edible mushrooms, making it an exceptionally important group ecologically and economically. However, the diversity of the species from China has not been fully elucidated. In this study, we conducted a phylogenetic analysis based on the internal transcribed spacer (ITS) regions, using Maximum Likelihood and Bayesian analyses, along with morphological observations of this genus. Four new species from China are proposed, viz., T. dactyliophora, T. lacunosa, T. petaloides, and T. pinnatifida. In addition, T. sikkimensis originally described from India is reported for the first time from China. Thelephora dactyliophora, T. pinnatifida, and T. sikkimensis are distributed in subtropical forests and mainly associated with plants of the families Fagaceae and Pinaceae. Thelephora lacunosa and T. petaloides are distributed in tropical to subtropical forests. Thelephora lacunosa is mainly associated with plants of the families Fagaceae and Pinaceae, while T. petaloides is mainly associated with plants of the family Fagaceae. Line drawings of microstructures, color pictures of fresh basidiomes, and detailed descriptions of these five species are provided.

The tyrosine phosphorylation of GRK2 is responsible for activated D2R-mediated insulin resistance.

Dopamine D2 receptor (D2R) plays a key role in the regulation of glucose homeostasis by stimulating the secretion of many glucoregulatory hormones. Insulin resistance (IR) is associated with the pathogenesis of metabolic disorders which occurs when PI3K/Akt signaling pathway is downregulated. However, the potential involvement of D2R in insulin resistance remains unclear. In the present study, we investigated the regulation of glucose transport by D2-like receptors and discovered that activation of D2R, but not D3R or D4R, suppressed insulin-induced 2-DOG uptake and Glut4 membrane translocation in a GRK2- and Src-dependent manner. Further study revealed that activation of D2R inhibits insulin-induced phosphorylation of Akt at Thr308 and Ser473, which are hallmarks of its kinase activity, by increasing the interaction of tyrosine phosphorylated GRK2 with Akt and then preventing Akt from interacting with PDK1. Thus, this study demonstrates that Src mediated GRK2 tyrosine phosphorylation is an essential physiological event that mediates the roles of D2R in insulin resistance.