分类: 生物学 >> 生物物理学 >> 免疫学 提交时间: 2016-05-12
摘要: Mucosal immunity protects a host from intestinal inflammation and infection and is profoundly influenced by symbiotic bacteria. Here we report that in mice symbiotic bacteria directed selective cargo sorting in Paneth cells to promote symbiosis through Nod2, a cytosolic bacterial sensor, and the multifunctional protein kinase LRRK2, both encoded by inflammatory bowel disease (IBD)-associated genes. Commensals recruited Nod2 onto lysozyme-containing dense core vesicles (DCVs), which was required for DCV localization of LRRK2 and a small GTPase, Rab2a. Deficiency of Nod2, LRRK2 or Rab2a or depletion of commensals resulted in lysosomal degradation of lysozyme. Thus, commensal bacteria and host factors orchestrate the lysozyme-sorting process to protect the host from enteric infection, implicating Paneth cell dysfunction in IBD pathogenesis.
分类: 生物学 >> 生物物理学 提交时间: 2016-05-11
摘要: Maize chlorotic mottle virus (MCMV) is the only member of the Machlomovirus genus in the family Tombusviridae. Here, we obtained the Cryo-EM structure of MCMV by single particle analysis with most local resolution at approximately 4 angstrom. The C alpha backbone was built based on residues with bulky side chains. The resolved C-terminus of the capsid protein subunit and obvious openings at the 2-fold axis demonstrated the compactness of the asymmetric unit, which indicates an important role in the stability of MCMV. The Asp116 residue from each subunit around the 5-fold and 3-fold axes contributed to the negative charges in the centers of the pentamers and hexamers, which might serve as a solid barrier against the leakage of genomic RNA. Finally, the loops most exposed on the surface were analyzed and are proposed to be potential functional sites related to MCMV transmission. (C) 2015 Elsevier Inc. All rights reserved.
提交时间: 2017-05-02
摘要: Various low ratios of triplet iridium complexes [0, 0.5, 1, 1.5, 2.5, and 5 mol%] are conjugated to the backbone of the famous champion donor polymer PTB7. At the same conditions, the power conversion efficiency for polymer containing 1% of Ir increases b