Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.

UniProt release 2018_05

新疆十一选五开奖结果 www.6nbnc.cn Published May 23, 2018

Headline

Selenium vs. Sulfur: and the winner is...

Selenium is a chemical element that, in trace amounts, is essential for cellular function in many, though not all, organisms from all kingdoms of life. Proteins incorporate selenium as selenocysteine (Sec), where selenium replaces the sulfur of cysteine, when an UGA stop codon is “recoded” by a Sec-tRNA and a selenocysteine insertion sequence (SECIS) within target mRNA. Sec is indispensable for mammalian life and deficiency in Sec-tRNA is embryonic-lethal (shortly after implantation) in mice, yet this process is complex, inefficient and energetically costly. Why then does Mother Nature continue to produce selenoproteins in spite of these drawbacks?

Recent work from Ingold et al. suggests that one reason may be the ability of selenium to protect cells from a specific form of oxidative stress leading to cell death. The authors focused on the phospholipid hydroperoxide glutathione peroxidase GPX4, an essential selenoprotein and the only one whose knockout phenotype mimics that of Sec-tRNA gene disruption. GPX4 catalyzes the reduction of toxic lipid hydroperoxides formed when ferrous iron is imported into cells in the presence of reactive oxygen species produced during aerobic metabolism. If left unchecked, lipid peroxides can spontaneously propagate, directly damaging membranes or generating other toxic products, leading to a specific form of cell death, called ferroptosis. Mice in which the active site of GPX4 (Sec-73) is replaced by cysteine (GPX4-Cys) develop normally, but experience fatal seizures 2-3 weeks after birth. This phenotype is due to the lack of parvalbumin-positive GABAergic interneurons, which are important regulators of cortical network excitability. Hence the presence of Sec is essential for specific developmental events, such as the maturation of a specific class of neurons. In adult mice, the conditional expression of the GPX4-Cys mutant did not show any peculiar phenotype.

Cys substitution greatly reduces GPX4 activity, although it does not abolish it. In the presence of increasing levels of H2O2, GPX4-Cys readily undergoes irreversible oxidation and the mutant GPX4-Cys cells become exquisitely sensitive to peroxide-induced ferroptosis. In conclusion, the critical advantage of selenolate-versus thiolate-based catalysis may lie in its resistance to overoxidation when cells increase their metabolic rates and mitochondrial H2O2 production.

Selenium was discovered in 1817, almost exactly 200 years ago, and it is quite exciting to celebrate this anniversary with a new discovery about its role in higher organisms. As of this release, the updated GPX4 entries are publicly available.

Changes to the controlled vocabulary of human diseases

New diseases:

Deleted diseases

  • Epidermolysis bullosa dystrophica, Hallopeau-Siemens type
  • Epidermolysis bullosa dystrophica, Pasini type

Changes to the controlled vocabulary for PTMs

New term for the feature key ‘Modified residue’ (‘MOD_RES’ in the flat file):

  • Pyruvic acid (Tyr)

UniRef news

GO annotation to UniRef90 and UniRef50 clusters (also in clusters with one member)

In release 2017_05, we announced the addition of Gene Ontology (GO) annotations for UniRef90 and UniRef50 clusters: In this first approach, GO terms were assigned to clusters with at least 2 members, and a GO term was added to a cluster when it was found in all UniProtKB members, or when it was a common ancestor of at least one GO term of each member.

As of this release, 2018_05, we also adding GO annotations to UniRef90 and UniRef50 singleton clusters, i.e. clusters that have only one member. These clusters inherit the GO terms of their single member.

UniProt is an ELIXIR core data resource
Main funding by: National Institutes of Health

We'd like to inform you that we have updated our 新疆十一选五开奖结果 to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.

Do not show this banner again
  • 安徽多地已试点保障房“共有产权” 2019-06-26
  • 淮南老市政府大院已更新改造 未来将变身街边广场 2019-06-26
  • 中国是亚洲和平的基石 2019-06-25
  • “藏族院士”多吉:大自然是慷慨的,也是有原则的 2019-06-25
  • 暴瘦50斤,70岁的她爱穿比基尼,活得比少女还滋润! 2019-06-24
  • 比利时并不轻松地击败巴拿马 2019-06-23
  • 我们说国企产权不明晰就是公有制搞市场经济才会出现不明晰产权,这就说明我们还没有明晰产权建立市场经济就在搞市场经济,才会出现产权不明晰这个问题,才会导致公有制变成 2019-06-22
  • 长安街知事:中央督查组对党政一把手动真格 2019-06-21
  • “三聚氰胺”受害儿童父亲敲诈案再审:不构成犯罪 2019-06-20
  • 县名解析:晋中介休市地名来历 2019-06-19
  • 专题--河北频道--人民网 2019-06-18
  • 鹰潭高新区思想解放添发展动力 2019-06-18
  • 中粮名庄荟国际酒业有限公司总经理李士祎做客人民网 2019-06-17
  • 在学习中进步。[奋斗] 2019-06-16
  • [视频]习近平打老虎动漫续集:当官要对自己狠一点 2019-06-15
  • 2019最新买马资料 广东爱彩乐彩票网 踢足球图片简笔画人物 网上购买吉林11选5 3d009期心水论坛 海南环岛赛彩票 开奖点 乒乓球台长度 海涛平特论坛传奇 彩票官网软件下载 双色球中奖查询 一尾中特期期淮 云南快乐十分开奘结果 金狐真钱诈金花 福建体育彩票论坛首页 中国足彩网澳客