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Yeh, F.

Publications and source records attributed to Yeh, F..

3 recordsLinked to original sources

Database Permeating through Time, Space, and Medicine: A sequence, structure, and clinical compilation and comparison of transmembrane amino acids in VGL ion channels

Ion channels of the VGL superfamily are extremely diverse in their physiological roles - critical in all excitable cells. Mutations in these channels can cause clinical deficits and symptomologies. With recent advances in sequencing and structural data in the past 30 years, there is a plethora of bioinformatic information that experimentalists can utilize to draw hypotheses about structure and function. However, there is no cohesive database that has compiled this data and presents it in an easily accessible and avoids the confounds of close evolutionary lineages. Here, we seek to fill this gap in resources by compiling and comparing groups of sequences and structures across many channels of the VGL superfamily. Additionally, we corroborate the well-conserved amino acid positions with previous experimental work as well as put forth some understudied but well-conserved amino acid positions that might be fundamental to the certain generalizable mechanisms present in the VGL superfamily channels. To further lend evidence to understudied positions being critical to certain generalizable mechanisms, we also compiled clinical mutation data at these positions across many channels to show the likely functional relevance of these positions. Finally, we will make all of the alignments and resources we generated publicly available at https://github.com/Frank-Yeh-95/VGLDatabaseCompilation for ease of hypothesis generation.

biophysics↗

Elasticity and Thermal Stability are Key Determinants of Hearing Rescue by Mini-Protocadherin-15 Proteins

Protocadherin-15 is a core protein component of inner-ear hair-cell tip links pulling on transduction channels essential for hearing and balance. Protocadherin-15 defects can result in non-syndromic deafness or Usher syndrome type 1F (USH1F) with hearing loss, balance deficits, and progressive blindness. Three rationally engineered shortened versions of protocadherin-15 (mini-PCDH15s) amenable for gene therapy have been used to rescue function in USH1F mouse models. Two can successfully or partially rescue hearing, while another one fails. Here we show that despite varying levels of hearing rescue, all three mini-PCDH15 versions can rescue hair-cell mechanotransduction. Negative-stain electron microscopy shows that all three versions form dimers like the wild-type protein, while crystal structures of some engineered fragments show that these can properly fold and bind calcium ions essential for function. In contrast, simulations predict distinct elasticities and nano differential scanning fluorimetry shows differences in melting temperature measurements. Our data suggest that elasticity and thermal stability are key determinants of sustained hearing rescue by mini-PCDH15s.

bioengineering↗

Insights from the IronTract challenge: optimal methods for mapping brain pathways from multi-shell diffusion MRI

Limitations in the accuracy of brain pathways reconstructed by diffusion MRI (dMRI) tractography have received considerable attention. While the technical advances spearheaded by the Human Connectome Project (HCP) led to significant improvements in dMRI data quality, it remains unclear how these data should be analyzed to maximize tractography accuracy. Over a period of two years, we have engaged the dMRI community in the IronTract Challenge, which aims to answer this question by leveraging a unique dataset. Macaque brains that have received both tracer injections and ex vivo dMRI at high spatial and angular resolution allow a comprehensive, quantitative assessment of tractography accuracy on state-of-the-art dMRI acquisition schemes. We find that, when analysis methods are carefully optimized, the HCP scheme can achieve similar accuracy as a more time-consuming, Cartesian-grid scheme. Importantly, we show that simple pre- and post-processing strategies can improve the accuracy and robustness of many tractography methods. Finally, we find that fiber configurations that go beyond crossing (e.g., fanning, branching) are the most challenging for tractography. The IronTract Challenge remains open and we hope that it can serve as a valuable validation tool for both users and developers of dMRI analysis methods.

neuroscience↗