A cysteine-based molecular code informs collagen C-propeptide assembly
Fundamental questions regarding collagen biosynthesis, especially with respect to the molecular origins of homotrimeric versus heterotrimeric assembly, remain unanswered. Here, we demonstrate that the presence or absence of a single cysteine in type-I collagen's C-propeptide domain is a key fac...
Main Authors: | , , , , , , , |
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Other Authors: | , |
Format: | Article |
Language: | English |
Published: |
Springer Science and Business Media LLC,
2020-05-28T17:31:58Z.
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Subjects: | |
Online Access: | Get fulltext |
Summary: | Fundamental questions regarding collagen biosynthesis, especially with respect to the molecular origins of homotrimeric versus heterotrimeric assembly, remain unanswered. Here, we demonstrate that the presence or absence of a single cysteine in type-I collagen's C-propeptide domain is a key factor governing the ability of a given collagen polypeptide to stably homotrimerize. We also identify a critical role for Ca2+ in non-covalent collagen C-propeptide trimerization, thereby priming the protein for disulfide-mediated covalent immortalization. The resulting cysteine-based code for stable assembly provides a molecular model that can be used to predict, a priori, the identity of not just collagen homotrimers, but also naturally occurring 2:1 and 1:1:1 heterotrimers. Moreover, the code applies across all of the sequence-diverse fibrillar collagens. These results provide new insight into how evolution leverages disulfide networks to fine-tune protein assembly, and will inform the ongoing development of designer proteins that assemble into specific oligomeric forms. National Science Foundation (U.S.) (Grant NSF-0070319) National Science Foundation (U.S.). Center for Science of Information (Grant P30-ES002109) National Institutes of Health (U.S.) (Grant R03AR067503) National Institutes of Health (U.S.) (Grant 1R01AR071443) National Institutes of Health (U.S.). Ruth Kirschstein Predoctoral Fellowship (1F31AR067615) |
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