This perspective begins with a speculative consideration of the properties of the earliest proteins to appear during evolution. What did these primitive proteins look like, and how were they of benefit to early forms of life? I proceed to hypothesize that primitive proteins have been preserved through evolution and now serve diverse functions important to the dynamics of cell morphology and biological regulation. The primitive nature of these modern proteins is easy to spot. They are composed of a limited subset of the 20 amino acids used by traditionally evolved proteins and thus are of low sequence complexity. This chemical simplicity limits protein domains of low sequence complexity to forming only a crude and labile type of protein structure currently hidden from the computational powers of machine learning. I conclude by hypothesizing that this structural weakness represents the underlying virtue of proteins that, at least for the moment, constitute the dark matter of the proteome.

中文翻译：

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低序列复杂性的蛋白质结构域——蛋白质组的暗物质

这种观点始于对进化过程中出现的最早蛋白质的特性的推测性考虑。这些原始蛋白质是什么样子的，它们对早期生命形式有什么好处？我继续假设原始蛋白质在进化过程中得到了保留，现在具有对细胞形态和生物调节的动态重要的多种功能。这些现代蛋白质的原始性质很容易被发现。它们由传统进化蛋白质使用的 20 种氨基酸的有限子集组成，因此序列复杂性较低。这种化学简单性限制了低序列复杂性的蛋白质结构域，只能形成目前隐藏在机器学习计算能力之外的原始且不稳定类型的蛋白质结构。最后，我假设这种结构弱点代表了蛋白质的潜在优点，至少在目前，蛋白质构成了蛋白质组的暗物质。