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111.
Crystal structure of Ufc1, the Ufm1-conjugating enzyme   总被引:2,自引:0,他引:2  
Ubiquitin and ubiquitin-like protein-conjugating enzymes play central roles in posttranslational modification processes. The ubiquitin-fold modifier 1 (Ufm1), one of a variety of ubiquitin-like modifiers, is covalently attached to target proteins via Uba5 and Ufm1-conjugating enzyme 1 (Ufc1), which are analogous to the E1 and E2 ubiquitylation enzymes. As Ufm1-related proteins are conserved in metazoa and plants, the Ufm1 system likely plays important roles in various multicellular organisms. Herein, we report the X-ray structure of human Ufc1 determined at 1.6 A resolution. The Ufc1 structure comprises a canonical E2 domain and an additional N-terminal domain. The Uba5 binding site on Ufc1 was assigned by structural comparison of Ufc1 and Ubc12 and related mutational analyses. In addition, we show that the N-terminal unique domain of Ufc1 contributes to thermal stability.  相似文献   
112.
Milk fermented with a starter containing Lactobacillus helveticus and Saccharomyces cerevisiae is drunk on a daily basis by many people in Japan and has several beneficial effects. We studied the influence of this fermented milk product on muscle damage after prolonged exercise in rats. Wistar rats were divided into four groups: rested controls, rested rats given fermented milk diet, exercised rats and exercised rats given fermented milk diet. After 3 weeks of acclimatization, both exercise groups were made to run on a treadmill at 26 m/min for 60 min. Exercise increased the serum creatine kinase level, as well as myeloperoxidase activity and the level of thiobarbituric-acid-reactive substances in the gastrocnemius muscle after 24 h. These changes were ameliorated by intake of fermented milk. An increase of CINC-1 was also ameliorated by fermented milk. Furthermore, milk diet increased the mRNA and protein levels of protective proteins such as antioxidants and chaperone proteins. These results indicate that fermented milk can ameliorate delayed-onset muscle damage after prolonged exercise, which is associated with an increased antioxidant capacity of muscles.  相似文献   
113.
A new series of 1beta-methyl carbapenems possessing a 6,7-disubstituted imidazo[5,1-b]thiazol-2-yl group directly attached to the C-2 position of the carbapenem nucleus was prepared, and the activities of these compounds against methicillin-resistant Staphylococcus aureus (MRSA) were evaluated. To study the effect of basic moieties on anti-MRSA activity, we introduced an amino, or imino, or amidino group at the 6-position of imidazo[5,1-b]thiazole in place of the carbamoylmethyl moiety of CP5068. Anti-MRSA activities of almost all basic group-substituted carbapenems were improved, though some of the compounds showed stronger acute toxicity in mice than IPM. In order to decrease the toxicity without decreasing the activity, we introduced various additional functionalities around the basic moiety. Finally, we obtained CP5484, which has excellent anti-MRSA activity and low acute toxicity.  相似文献   
114.
Journal of Ethology - Males of the Japanese scorpionfly, Panorpa japonica, often perform male–male competitions for food to offer to females as a nuptial gift. Previous studies have suggested...  相似文献   
115.
Journal of Ethology - Circadian rhythm is an important factor for long-distance movement in insect species. Previous studies have shown the relationship between movement and circadian rhythm,...  相似文献   
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Background

Paraneoplastic retinopathy (PR), including cancer-associated retinopathy (CAR) and melanoma-associated retinopathy (MAR), is a progressive retinal disease caused by antibodies generated against neoplasms not associated with the eye. While several autoantibodies against retinal antigens have been identified, there has been no known autoantibody reacting specifically against bipolar cell antigens in the sera of patients with PR. We previously reported that the transient receptor potential cation channel, subfamily M, member 1 (TRPM1) is specifically expressed in retinal ON bipolar cells and functions as a component of ON bipolar cell transduction channels. In addition, this and other groups have reported that human TRPM1 mutations are associated with the complete form of congenital stationary night blindness. The purpose of the current study is to investigate whether there are autoantibodies against TRPM1 in the sera of PR patients exhibiting ON bipolar cell dysfunction.

Methodology/Principal Findings

We performed Western blot analysis to identify an autoantibody against TRPM1 in the serum of a patient with lung CAR. The electroretinograms of this patient showed a severely reduced ON response with normal OFF response, indicating that the defect is in the signal transmission between photoreceptors and ON bipolar cells. We also investigated the sera of 26 patients with MAR for autoantibodies against TRPM1 because MAR patients are known to exhibit retinal ON bipolar cell dysfunction. Two of the patients were found to have autoantibodies against TRPM1 in their sera.

Conclusion/Significance

Our study reveals TRPM1 to be one of the autoantigens targeted by autoantibodies in at least some patients with CAR or MAR associated with retinal ON bipolar cell dysfunction.  相似文献   
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