Structure of the second PDZ domain from human zonula occludens 2.

Human zonula occludens 2 (ZO-2) protein is a multi-domain protein that consists of an SH3 domain, a GK domain and three copies of a PDZ domain with slight divergence. The three PDZ domains act as protein-recognition modules that may mediate protein assembly and subunit localization. The crystal structure of the second PDZ domain of ZO-2 (ZO-2 PDZ2) was determined by molecular replacement at 1.

Domain-swapped dimerization of the second PDZ domain of ZO2 may provide a structural basis for the polymerization of claudins.

Zonula occludens proteins (ZOs), including ZO1/2/3, are tight junction-associated proteins. Each of them contains three PDZ domains. It has been demonstrated that ZO1 can form either homodimers or heterodimers with ZO2 or ZO3 through the second PDZ domain.

Solution structure of the second bromodomain of Brd2 and its specific interaction with acetylated histone tails.

Background: Brd2 is a transcriptional regulator and belongs to BET family, a less characterized novel class of bromodomain-containing proteins. Brd2 contains two tandem bromodomains (BD1 and BD2, 46% sequence identity) in the N-terminus and a conserved motif named ET (extra C-terminal) domain at the C-terminus that is also present in some other bromodomain proteins. The two bromodomains have been shown to bind the acetylated histone H4 and to be responsible for mitotic retention on chromosomes, which is probably a distinctive feature of BET family proteins.

[Changes of connexin 43 in rabbit with early myocardial ischemia].

Objective: To reveal gap junction connexin 43 (Cx43) in rabbit with early myocardial ischemia.

Methods: The left coronary arteries were ligated to create early myocardial ischemia. Cx43 was visualized by use of SP immunohistochemical method (IHC) and Colloidal gold of the electron microscopy, and a comparison was made between the experiment group and the control group.

[The changes of water channel protein 1 in the lungs of the drown rat].

Objective: To observe water channel 1 protein in the lungs of the drown rat.

Methods: Immunohistochemical method and Colloidal gold of the electron microscopy were used to observe the location of aquaporin1(AQP1) on the rat lung tissue between the experiment group and control group.

Results: The positive expression of AQP1 was seen in the capillary endotheliocyte of the interstitium and around bronchi and in the alveolar endothelial cells.