BRICHOS - a superfamily of multidomain proteins with diverse functions.
BRICHOS - a superfamily of multidomain proteins with diverse functions.
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DOI：
10.1186/1756-0500-2-180
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发表时间：
2009-09-11
影响因子：
1.8
通讯作者：
Persson B
中科院分区：
文献类型：
--
作者：
Hedlund J;Johansson J;Persson B
BRICHOS结构域存在于8个蛋白质家族中，具有广泛的功能和多种疾病相关性，如呼吸窘迫综合征、痴呆和癌症。该结构域本身被认为具有分子伴侣功能，实际上其中三个家族与淀粉样蛋白的形成有关，但其结构和许多功能特性仍然未知。BRICHOS超家族中的蛋白质具有四个具有不同性质的区域。我们分析了BRICHOS蛋白质的序列保守性，氨基酸残基的性质，天然的障碍和二级结构的预测。残基保守性在区域之间显示出很大的差异，并且不同家族之间残基保守性的分布在区域内可以有很大的差异。BRICHOS蛋白的二级结构预测显示出显着的一致性，即使在序列保守性低，似乎有一点天然的障碍。保存率的差异很大，表明不同地区和科之间存在不同的功能限制。我们提出了三个以前未知的BRICHOS家庭; A组，这可能是祖先的ITM2家庭;组B，这是一个密切的关系到的gastrokine家庭，和C组，这似乎是一个真正的新的，不相交的BRICHOS家庭。C组的C-末端区域在从鱼到人的所有物种中具有几乎相同的序列，并且似乎是该家族所独有的，表明关键的功能或结构特性。
The BRICHOS domain has been found in 8 protein families with a wide range of functions and a variety of disease associations, such as respiratory distress syndrome, dementia and cancer. The domain itself is thought to have a chaperone function, and indeed three of the families are associated with amyloid formation, but its structure and many of its functional properties are still unknown. The proteins in the BRICHOS superfamily have four regions with distinct properties. We have analysed the BRICHOS proteins focusing on sequence conservation, amino acid residue properties, native disorder and secondary structure predictions. Residue conservation shows large variations between the regions, and the spread of residue conservation between different families can vary greatly within the regions. The secondary structure predictions for the BRICHOS proteins show remarkable coherence even where sequence conservation is low, and there seems to be little native disorder. The greatly variant rates of conservation indicates different functional constraints among the regions and among the families. We present three previously unknown BRICHOS families; group A, which may be ancestral to the ITM2 families; group B, which is a close relative to the gastrokine families, and group C, which appears to be a truly novel, disjoint BRICHOS family. The C-terminal region of group C has nearly identical sequences in all species ranging from fish to man and is seemingly unique to this family, indicating critical functional or structural properties.