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 Published May 23, 2018


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
  • 湖口县公安局开展集中整治城区飙车行动 2019-03-19
  • 【高清】福州:体验身边的高科技 2019-03-18
  • 新疆伊犁:薰衣草香飘万里 “紫色经济”成产业 2019-03-17
  • 安踏、特步齐发澄清公告 称沽空报告不属实、具有误导性 2019-03-17
  • 曹建明:推进平安中国建设,确保国家长治久安、人民安居乐业 2019-03-16
  • 云南女子饲养小猴子5年 竟是国家一级保护动物熊猴 2019-03-16
  • 图解:习近平的《人民日报》情缘 2019-03-15
  • 是建立市场经济才搞市场经济,不是搞市场经济,我们如何正确认识这个问题? 2019-03-14
  • 全世界人民都要尊重人类社会发展规律即从过去资本主义社会财富私有制经过现代社会财富公有制和私有制并存而发展到未来共产主义社会财富公有制。 2019-03-13
  • 河南焦作市2018年面向国内外引进高层次急需紧缺人才公告 2019-03-13
  • 足球界最丑十大球星:小罗第4!鲁尼第3 里贝里仅第6! ——凤凰网房产 2019-03-12
  • 公安部严查制售高科技作弊专用器材犯罪 2019-03-11
  • 从唐老鸭到疯狂动物城:卡通毛皮七十年 2019-03-10
  • 文化山西:风华长城岁月歌 2019-03-09
  • 世卫组织更新《国际疾病分类》 游戏成瘾列入精神疾病 2019-03-09
  • 938| 458| 438| 109| 880| 953| 201| 751| 16| 998|