Negative regulation of AMPK signaling by high glucose via E3 ubiquitin ligase MG53

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Human pescadillo induces large-scale chromatin unfolding

Pescadillo was initially identified in a genetic screen for mutations that affect embryonic develop-ment of the zebrafish Daniorerio[1]. Pescadillo-/- ze-brafish mutants showed abnormal embryonic devel-opment such as reduced brain, eye size and a lack of extension of the jaw on developmental day 3. Further study showed that the Pescadillo protein is mainly distributed in tissues containing a significant number of proliferating cells and dramatically elevated in ma-lignant human astrocytomas an…     

Ischemia impairs the association between connexin 43 and M3 subtype of acetylcholine muscarinic receptor (M3-mAChR) in ventricular myocytes.

We used Western blot analysis to examine the expression of connexin 43 and M2/M3 acetylcholine muscarinic receptors (mAChR) and their interaction in ventricular myocytes from control and the ischemic heart. We confirmed that the connexin 43 and M2/ M3-mAChR were expressed in ventricular myocytes. Moreover, we showed that M3-mAChR was expressed in non-glycosylated (72 kDa) and glycosylated forms (115 kDa). Immunostaining showed that connexin 43 is closely associated with M3-mAChR in parts of cell membranes of myocytes. Immunoprecipitation of lysate of cardiac myocytes with M2/M3-mAChR antibody pulled down a 44 kDa protein recognized by connexin 43 antibody. Ischemia increased the expression of M3-mAChR in myocytes. The ischemiainduced increase in the M3-mAChR expression was specific because ischemia did not affect the expression of M1, M2, M4 and M5- mAChR in the heart. On the other hand, ischemia decreased the expression of connexin 43 in myocardium. We also examined the effect of ischemia on the interaction between M2/M3-mAChR and connexin 43. Ischemia suppressed the association of M3-mAChR with connexin 43 but did not affect the association of connexin 43 with M2-mAChR. Administration of choline before ischemia not only partially restored the expression of connexin 43 but also attenuated the ischemia-induced suppression of the association between connexin 43 and M3-mAChR. We conclude that connexin 43 interacts with M2/M3-mAChR and that ischemia specifically impairs the association between M3-mAChR and connexin 43.     

The dynamic distribution of fluoro-gold and its interrelation with neural nitric oxide synthase following intracerebroventricular injection into rat brain

We mapped the dynamic distribution of fluoro-gold (FG) within rat brain following intracerebroventricular (icv) injection into the lateral ventricle and observed its interrelation with neural nitric oxide synthase (nNOS) using FG fluorescent microphotography combined with nNOS immunohistochemistry. We also detected the amount of icv administered FG entering the peripheral circulation using a fluorescence microplate assay. The degree of periventricular penetration of FG was significantly increased over time. At 2 min after icv injection, FG primarily labeled the choroid plexus in the lateral and third ventricles, with limited penetration into the ependyma and the subependyma of the same ventricles. Some FG/nNOS-double labeled cerebrospinal fluid-contacting neurons were observed in these ventricles as well. At 15 and 30 min, FG penetrated mainly into forebrain ventricular organs and parenchymal structures. Many FG/nNOS double labeled neurons were found at each of these sites. In addition, at 30 min intense FG labeling was found in the hypophysis, while limited periventricular penetration of FG was detected in the hindbrain circumventricular areas. In the peripheral circulation, a low concentration of FG was detected 2 min after icv injection. The concentration increased slowly, peaked at 20 min, then gradually decreased until the end of the experiment at 30 min. These findings indicate that dynamic penetration of icv administrated agents into the periventricular tissues and peripheral circulation should be considered when designing icv experiments.     

Expression level of histone deacetylase 2 correlates with occurring of chronic obstructive pulmonary diseases

Chronic obstructive pulmonary disease (COPD) is associated with chronic severe airway inflammation and causes increasing global health problems. New biological markers for COPD prediction and prognosis are urgently necessary. Previous studies indicate that histone deacetylases (HDACs) play essential roles in COPD. This study is to investigate if HDAC2 levels can be used as a promising, easily detected biomarker of COPD. In this paper, 49 COPD patients were enrolled and 42 healthy individuals (smokers or non-smokers) were used as healthy controls. Human bronchial epithelial cells derived from non-smokers, smokers, or COPD patients were grown in primary cultures. Total proteins were harvested from lung tissues or bronchial epithelial cells and then subjected to immunoblot analyses of HDAC2, HDAC3, and HDAC5. Quantitative RT-PCR analysis of HDAC2, HDAC3, and HDAC5 mRNA levels in tissues or cells were also preformed. We found that among the three HDAC proteins, the mRNA and protein levels of HDAC2, but not HDAC3 and HDAC5, in the tissues or cultured cells from patients have a significant correlation with development and prognosis of COPD. These results suggested that HDAC2 levels may serve as a promising, easily detected biomarker of COPD.     

A novel wheat α‐amylase inhibitor gene,TaHPS, significantly improves the salt and drought tolerance of transgenic Arabidopsis

On the basis of microarray analyses of the salt‐tolerant wheat mutant RH8706‐49, a previously unreported salt‐induced gene, designated as TaHPS [Triticum aestivum hypothetical (HPS)‐like protein], was cloned. Real‐time quantitative polymerase chain reaction analyses showed that expression of the gene was induced by abscisic acid, salt and drought. The encoded protein was found to be localized mainly in the plasma membranes. Transgenic Arabidopsis plants overexpressing TaHPS were more tolerant to salt and drought stresses than non‐transgenic wild‐type (WT) plants. Under salt stress, the root cells of the transgenic plants secreted more Na⁺ and guard cells took up more Ca²⁺ ions. Compared with wild‐type plants, TaHPS‐expressing transgenic plants showed significantly lower amylase activity and glucose and malic acid levels. Our results showed that the expression of TaHPS inhibited amylase activity, which subsequently led to a closure of stomatal apertures and thus improved plant tolerance to salt and drought.     

Malleola tibetica sp. nov. (Aeridinae,Orchidaceae) from Tibet,China

Malleola tibetica, a new species from southeastern tropical Tibet, China, is described and illustrated. Morphologically, the new species is closely related to M. dentifera, but differs from it by having uniformly green leaves, flowers with entire lateral lobes of the lip and a basally thickened mid‐lobe, and a column that is densely cristaline‐papillose adaxially.     

A genome walking strategy for the identification of nucleotide sequences adjacent to known regions

To identify the transposon insertion sites in a soil actinomycete, Saccharopolyspora spinosa, a genome walking approach, termed SPTA-PCR, was developed. In SPTA-PCR, a simple procedure consisting of TA cloning and a high stringency PCR, following the single primer-mediated, randomly-primed PCR, can eliminate non-target DNA fragments and obtain target fragments specifically. Using SPTA-PCR, the DNA sequence adjacent to the highly conserved region of lectin coding gene in onion plant, Allium chinense, was also cloned.