No abstract available.
Animals ; Female ; Ovary* ; Rats* ; Serine Proteases* ; Serine*

Kunitz-type serine protease inhibitors are a class of ubiquitous protease inhibitors, which play important roles in various life activities. The structures of such inhibitors are generally stable, and are usually characterized by the presence of one or several Kunitz domains in tandem, which are able to bind to serine proteases in a manner similar to substrate binding, thereby inhibiting enzyme activity. In terms of function, Kunitz-type serine protease inhibitors are involved in processes such as blood coagulation and fibrinolysis, tumor immunity, inflammation regulation, and resistance to bacterial and fungal infections. This article summarizes the advances of Kunitz-type serine protease inhibitors and provides new ideas for the development of novel Kunitz-type serine protease inhibitors.
Protease Inhibitors ; Serine Proteases ; Serine Proteinase Inhibitors

No abstract available.
Humans* ; Keratinocytes* ; Protein-Serine-Threonine Kinases* ; Serine* ; Threonine*

Humans ; Phosphorylation ; Serine ; Protein Serine-Threonine Kinases/metabolism* ; Spasms, Infantile

Animals ; Atherosclerosis ; Humans ; Serine Proteinase Inhibitors ; Serpins

L-Homoserine is a non-essential amino acid that is often used as an important platform compound and additive in industrial production. To improve the production efficiency, a previously constructed L-homoserine producing strain E. coli H0-0 was used as a chassis for further metabolic modification. Firstly, the ppc and pyccgP458S genes were overexpressed to optimize the Kreb's cycle. Subsequently, thrAC1034T and lysCcgC932T were overexpressed to improve the product synthesis, followed by inactivation of iclR gene to reduce the accumulation of by-products. The introduction of three sucrose metabolism genes, scrA, scrB and scrK, enabled E. coli to ferment sucrose. The titer of L-homoserine increased from 3.2 g/L to 11.1 g/L.
Escherichia coli/genetics* ; Homoserine ; Metabolic Engineering ; Serine

Humans ; Phosphorylation ; Serine/metabolism* ; Protein Serine-Threonine Kinases/metabolism* ; Signal Transduction ; Neovascularization, Pathologic

In several human tumors, signal transducer and activator of transcription 3 (STAT3) and nuclear factor κB (NFκB) are activated and interact; how these STAT3–NFκB complexes are transported to the nucleus is not fully understood. In this study, we found that Rac1 was activated in starved cancer cells and that activated Rac1 coexisted with STAT3 and NFκB. Rac1 knockdown and overexpression of the dominant-negative mutant Rac1N19 inhibited the degradation of IκBα, an inhibitor of NFκB. MG132, an inhibitor of the ubiquitin proteasome pathway, increased the amount of non-phosphorylated IκBα, but not serine-phosphorylated IκBα, indicating that IκBα degradation by Rac1 in starved cancer cells is independent of IκBα serine phosphorylation by IKK. Rac1 knockdown also inhibited the nuclear translocation of STAT3–NFκB complexes, indicating that this translocation requires activated Rac1. We also demonstrated that the mutant STAT3 Y705F could form complexes with NFκB, and these unphosphorylated STAT3–NFκB complexes translocated into the nucleus and upregulated the activity of NFκB in starved cancer cells, suggesting that phosphorylation of STAT3 is not essential for its translocation. To our knowledge, this is the first study demonstrating the crucial role of Rac1 in the function of STAT3–NFκB complexes in starved cancer cells and implies that targeting Rac1 may have future therapeutic significance in cancer therapy.
Humans ; Phosphorylation ; Proteasome Endopeptidase Complex ; Serine ; STAT3 Transcription Factor ; Ubiquitin

Translationally controlled tumor proteins (TCTP) and SNF1- related protein kinase (SnRK1) are conserved and widely present in eukaryotic cells. TCTP regulates cell division, plant growth and development, and mediates plant resistance against pathogen infection. SnRK1 participates in a range of physiological processes including sugar metabolism and resistance to abiotic and biotic stresses. Previous work in our laboratory demonstrated that wheat TCTP can respond to Puccinia triticina infection and induce host defense responses. In order to further investigate the mechanism of TaTCTP in wheat resistance to Puccinia triticina infection, we used TAP (tandem affinity purification) and mass spectrometry to screen the potential interactants of TaTCTP. A SNF1- related protein kinase (SnRK1) was identified as a potential interacting protein of TaTCTP. The results of yeast two-hybrid assay showed that TCTP could interact with SnRK1 in yeast, and the yeast carrying TCTP and SnRK1 could grow on SD/-Leu/-Trp/-His/-Ade (SD/-LWHA) medium. The fluorescence signal of the interaction between TCTP and SnRK1 was found to be distributed in the cytoplasm in the Bi-fluorescense complementation experiment. Co-IP experiments further showed that TCTP and SnRK1 could interact in plant cells. This study lays an important foundation for further studying the mechanism of TaTCTP in the interaction between wheat and Puccinia triticina, and it play a great influence on further improving the molecular mechanism of wheat resistant to Puccinia triticina.
Basidiomycota ; Humans ; Neoplasms ; Protein Biosynthesis ; Protein-Serine-Threonine Kinases ; Triticum

OBJECTIVE: To analyze the expression level of the serum soluble E cadherin (SE-CAD) and Matriptase and its clinical significance for evaluation of the disease condtions and prognosis in patients with acute myeloid leukemia (AML). METHODS: One hundred and ten patients diagnosed as AML in our hospital were divided into 3 groups: newly diagnosed group (38 cases), remission group (40 cases) and recurrence group (32 cases). The expression levels of serum matriptase were detected by Western blot, and the expression levels of serum SE-CAD were detected by ELISA. The serum levels of serum SE-CAD and matriptase among 3 groups were compared. Followin-up for one year, according to the outcome of patients, all the patients were divided into 2 groups: the survival group and death group. The serum levels of SE-CAD and Matriptase were compared between 2 groups. The correlation of serum levels of SE-CAD and matriptase with the survival of AML patients was analyzed by multivariate Logistic analysis. The evaluation value of the serum levels of SE-CAD and matriptase for the prognosis of the patients with AML were analyzed by receiver operating characteristic curves (ROC). RESULTS: The serum levels of SE-CAD and matriptase were siginificantly different among 3 groups (P＜0.05). The serum levels of SE-CAD and matriptase in remission group were lowest (P＜0.05), and the serum levels of SE-CAD and matriptase were not different between newly diagnoses and recurrence groups (P＞0.05). Multivariate Logistic analysis showed that the serum levels of SE-CAD and matriptase were independent risk factors for the prognosis of AML patients (OR=3.157, P＜0.05, OR=2.426, P＜0.05). By follow-up for 1 year, the serum expression levels of SE-CAD and Matriptase in survival group were lower than that in death group. ROC curve showed that when the cut-off value of matriptase level was 0.73 and SE-CAD level was 3.42 ng/ml, the AUC of predictions for the poor prognosis in AML patients was 0.849 (P＜0.05), the sensitivity was 85.6% (95%CI: 0.810~0.924) and specificity was 89.6% (95%CI: 0.849~0.941). CONCLUSION The serum levels of SE-CAD and matriptase can perfectly evaluate the condition and short-term prognosis of the patients with AML.
Cadherins ; Humans ; Leukemia, Myeloid, Acute ; Prognosis ; Serine Endopeptidases