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Toll-like receptor-mediated NF-κB activation is a major innate immune reaction of vascular endothelial cells (ECs) in response to prooxidative and proinflammatory stimuli. We identified that TNF-α receptor-associated factor-interacting protein with a forkhead-associated domain (TIFA) is a regulator of priming (signal 1) and activating (signal 2) signals of nucleotide oligomerization domain-like receptor family pyrin domain-containing protein 3 (NLRP3) inflammasome in ECs. Oxidative and inflammatory stresses such as atheroprone flow and hyperlipidemia induce and activate TIFA in vitro and in vivo. For the priming of signal 1, sterol regulatory element-binding protein 2 transactivates TIFA, which in turn induces NF-κB activation and augments the transcription of NLRP3 inflammasome components. For the activation of signal 2, Akt is involved in TIFA Thr9 phosphorylation, which is essential for TIFA-TIFA homophilic oligomerization. Thr9 phosphorylation-dependent TIFA oligomerization facilitates the higher-order assembly of NLRP3 inflammasome, as indicated by the interaction between TIFA and caspase-1 in the activated ECs. Our results suggest that TIFA is a crucial mediator in the endothelial innate immune response by potentiating and amplifying NLRP3 inflammasome via augmenting signals 1 and 2.

Nucleolar protein interacting with the FHA domain of pKi-67 (NIFK) is a Ki-67-interacting protein. However, its precise function in cancer remains largely uninvestigated. Here we show the clinical significance and metastatic mechanism of NIFK in lung cancer. NIFK expression is clinically associated with poor prognosis and metastasis. Furthermore, NIFK enhances Ki-67-dependent proliferation, and promotes migration, invasion in vitro and metastasis in vivo via downregulation of casein kinase 1α (CK1α), a suppressor of pro-metastatic TCF4/β-catenin signaling. Inversely, CK1α is upregulated upon NIFK knockdown. The silencing of CK1α expression in NIFK-silenced cells restores TCF4/β-catenin transcriptional activity, cell migration, and metastasis. Furthermore, RUNX1 is identified as a transcription factor of CSNK1A1 (CK1α) that is negatively regulated by NIFK. Our results demonstrate the prognostic value of NIFK, and suggest that NIFK is required for lung cancer progression via the RUNX1-dependent CK1α repression, which activates TCF4/β-catenin signaling in metastasis and the Ki-67-dependent regulation in cell proliferation.

Phosphatidylinositol-specific phospholiphase C accepts a variety of alkyl and aryl inositol phosphates as substrates, making it a suitable enzyme for studying mechanism of phosphoryl transfer by probing the linear free-energy relationship. A study of Bronsted-type linear free-energy relationship (LFER) relationship to compare mechanisms of enzymatic and nonenzymatic reactions is conducted to assess the role of hydrophobicity in the leaving group as a general acid-enabling factor.

Research demonstrates that placing 2-aminopurine one base below the nascent base pair greatly enhances the signal intensity while placing it two bases below provides acceptable signal-to-noise ratio. The research findings are useful in the determination of kinetic constants for dNTP and catalytic magnesium incorporation, which is facilitated by DNA polymerase beta.

The established concept of high nucleotide incorporation fidelity by DNA polymerases suggests a new 'simplified' model. Research points out that the fidelity arises from differential substrate binding step at the transition state, which facilitates substrate selectivity by DNA polymerases.

Research has been conducted on the oncogenic protein gankyrin, containing ankyrin repeats. Results indicate that this protein is involved in the degradation and phosphorylation of the retinoblastoma gene product Rb.

The authors have evaluated the conceptual and analytical progress made since the publication of the pancreatic secreted phospholipase A (sub)2 survey. The purpose of this review is to focus on the methods of determining the parameters describing the interfacial turnover cycle events useful for the structure-function correlation for the specific reaction steps.

Research has been conducted on the stereoselectivity of the DNA polymerase. The pre-steady-state kinetic analysis of this stereoselectivity and its alteration by metal ions and by site-directed mutagenesis are discussed.

The Arg69 residue in phosphatidylinositol-specific phospholipase C not only binds the phosphate but positions it close to the 2-OH group of inositol in proper alignment for nucleophilic attack. The bidentate nature of this residue produces the large thio effects and stereoselectivity seen in this enzyme.

The Asp33, Arg69, and His32 residues of phosphatidylinositol-specific phospholipase C forms a triad that activates the phosphate group undergoing nucleophilic attack and protonates the leaving group. The formation of the triad depends on hydrophobic interactions between the enzyme and the leaving group.

Research on an intermediate structure of DNA polymerase beta shows that there is no rate-limiting step during conformational change. This enzyme has two metal-binding sites, one at the dNTP binding site and one at the catalytic site.