Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Tropoelastin and Elastin Assembly

doi: 10.3389/fbioe.2021.643110

Figure Lengend Snippet: Tropoelastin’s sequence and domain arrangement. Tropoelastin is a low complexity protein on both primary and secondary sequence levels. Its hydrophobic (pink) and cross-linking (blue) domains consist of repetitive motifs that contribute uniquely to elastin assembly. The hydrophobic domains contain aliphatic amino acids with proline variations that provide flexibility and the ability to assemble into higher order structures. The cross-linking domains are enriched for either Lys-Pro (KP) or Lys-Ala (KA) motifs and form cross-links that link growing tropoelastin chains during elastogenesis; note that exon 6 encodes a KA domain. Tropoelastin’s C-terminal domain 36 (yellow) does not fall into either category as it contains a distinct sequence capped with a Gly-Arg-Lys-Arg-Lys (GRKRK) motif and is primarily involved in cell interactions.

Article Snippet: The full-atomistic model of tropoelastin was developed based on replica exchange molecular dynamics (REMD) simulations, an accelerated sampling method for molecular dynamics ( ).

Techniques: Sequencing

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Tropoelastin and Elastin Assembly

doi: 10.3389/fbioe.2021.643110

Figure Lengend Snippet: Overview of the computational and experimental methodologies that have recently contributed to our understanding of elastic fiber assembly. The SAXS/SANS global shape of tropoelastin has been used to validate the full-atomistic computational model of tropoelastin through a geometric and topological comparison . Furthermore, the SAXS/SANS structure has been mapped to an elastic network model with tunable stiffness to probe the role of tropoelastin’s flexibility in fiber assembly . Meanwhile, modifications to the full-atomistic model have revealed the mechanisms that contribute to aberrant fiber structure that have been hypothesized to predispose patients to diseases such as acquired cutis laxa . Additionally, coarse-graining the full-atomistic model has allowed for the examination of mesoscale tropoelastin assembly and, in particular, deciphered the orientation of tropoelastin molecules that occurs during early stage assembly (inset image) . Future investigations will allow the bridging of the gap between mesoscale simulations and microscopically observed coacervation .

Article Snippet: The full-atomistic model of tropoelastin was developed based on replica exchange molecular dynamics (REMD) simulations, an accelerated sampling method for molecular dynamics ( ).

Techniques: Comparison

Journal: Frontiers in Bioengineering and Biotechnology

Article Title: Tropoelastin and Elastin Assembly

doi: 10.3389/fbioe.2021.643110

Figure Lengend Snippet: Stages of hierarchical assembly of elastic fibers. Tropoelastin monomers undergo self-assembly upon reaching the transition temperature through the aggregation of their hydrophobic domains . Assembly proceeds from a nucleation event and undergoes elongation in a step-wise manner to form a multimer which can occur in a head-to-tail fashion . Multimers may undergo further transitions, such as branching, to form spherules made of multimer aggregates . The spherules grow in size and are deposited onto the microfibril scaffold where they fuse into fibrillar structures . Elastic fibers are eventually formed after extensive cross-linking through a process termed maturation .

Article Snippet: The full-atomistic model of tropoelastin was developed based on replica exchange molecular dynamics (REMD) simulations, an accelerated sampling method for molecular dynamics ( ).

Techniques: