Learn More
Silent information regulator 2 (Sir2) proteins (sirtuins) are nicotinamide adenine dinucleotide-dependent deacetylases that regulate important biological processes. Mammals have seven sirtuins, Sirt1 to Sirt7. Four of them (Sirt4 to Sirt7) have no detectable or very weak deacetylase activity. We found that Sirt5 is an efficient protein lysine desuccinylase(More)
The initial desertification in the Asian interior is thought to be one of the most prominent climate changes in the Northern Hemisphere during the Cenozoic era. But the dating of this transition is uncertain, partly because desert sediments are usually scattered, discontinuous and difficult to date. Here we report nearly continuous aeolian deposits covering(More)
The Sir2 family of enzymes or sirtuins are known as nicotinamide adenine dinucleotide (NAD)-dependent deacetylases and have been implicated in the regulation of transcription, genome stability, metabolism and lifespan. However, four of the seven mammalian sirtuins have very weak deacetylase activity in vitro. Here we show that human SIRT6 efficiently(More)
Metallo-β-lactamases (MBLs) hydrolyze most β-lactam antibiotics, and bacteria containing this kind of enzyme pose a serious threat to the public health. The newly identified New Delhi MBL (NDM-1) is a new member of this family that shows tight binding to penicillin and cephalosporins. The rapid dissemination of NDM-1 in clinically relevant bacteria has(More)
Pathogenic microbes use effectors to enhance susceptibility in host plants. However, plants have evolved a sophisticated immune system to detect these effectors using cognate disease resistance proteins, a recognition that is highly specific, often elicits rapid and localized cell death, known as a hypersensitive response, and thus potentially limits(More)
KChIPs coassemble with pore-forming Kv4 alpha subunits to form a native complex in the brain and heart and regulate the expression and gating properties of Kv4 K(+) channels, but the mechanisms underlying these processes are unknown. Here we report a co-crystal structure of the complex of human Kv4.3 N-terminus and KChIP1 at a 3.2-A resolution. The(More)
BACKGROUND Most (70%) epithelial ovarian cancers (EOCs) are diagnosed late. Non-invasive biomarkers that facilitate disease detection and predict outcome are needed. The microRNAs (miRNAs) represent a new class of biomarkers. This study was to identify and validate plasma miRNAs as biomarkers in EOC. METHODOLOGY/PRINCIPAL FINDINGS We evaluated plasma(More)
The mechanisms underlying ovarian cancer cell resistance to cisplatin (CDDP) are not fully understood. MicroRNAs (miRNAs) play important roles in tumorigenesis and drug resistance. In this paper, we utilized microRNA array and real-time PCR to show that miR-93 is significantly up-regulated in cisplatin-resistant ovarian cancer cells. In vitro assays show(More)
Stecrisp from Trimeresurus stejnegeri snake venom belongs to a family of cysteine-rich secretory proteins (CRISP) that have various functions related to sperm-egg fusion, innate host defense, and the blockage of ion channels. Here we present the crystal structure of stecrisp refined to 1.6-angstrom resolution. It shows that stecrisp contains three regions,(More)
Cysteine dioxygenase is a mononuclear iron-dependent enzyme responsible for the oxidation of cysteine with molecular oxygen to form cysteine sulfinate. This reaction commits cysteine to either catabolism to sulfate and pyruvate or the taurine biosynthetic pathway. Cysteine dioxygenase is a member of the cupin superfamily of proteins. The crystal structure(More)