TY - JOUR
T1 - Deficiency in Kelch protein Klhl31 causes congenital myopathy in mice
AU - Papizan, James B.
AU - Garry, Glynnis A.
AU - Brezprozvannaya, Svetlana
AU - McAnally, John R.
AU - Bassel-Duby, Rhonda
AU - Liu, Ning
AU - Olson, Eric N.
N1 - Funding Information:
We thank Robyn Leidel for assistance and advice of the University of Texas Southwestern Electron Microscopy Core Facility, Andrew Lemoff for advice with the MS analysis, and James Richardson and Dennis Burns for help with histology and imaging. We are grateful to M. Arthur Moseley, Erik Soderblom, and the Duke University School of Medicine for the use of the Proteomics and Metabolo-mics Shared Resource. We would also like to thank Laura Ingle and Eric Plautz of the University of Texas Southwestern Neuro-Models Facility for grip-strength testing. We are very grateful to Jose Cabrerra for assistance with graphics. This work was supported in part by grants from the NIH (DK-099653, AR-067294, HL-130253 and HD-087351) and the Robert A. Welch Foundation (grant 1-0025 to ENO). NL was supported by a Beginning-Grant-In-Aid (13BGIA17150004) from the American Heart Association. JBP was supported by a Ruth L. Kirschstein NRSA F32 NIH training grant (5F32HL123323-03).
PY - 2017/10/2
Y1 - 2017/10/2
N2 - Maintenance of muscle structure and function depends on the precise organization of contractile proteins into sarcomeres and coupling of the contractile apparatus to the sarcoplasmic reticulum (SR), which serves as the reservoir for calcium required for contraction. Several members of the Kelch superfamily of proteins, which modulate protein stability as substratespecific adaptors for ubiquitination, have been implicated in sarcomere formation. The Kelch protein Klhl31 is expressed in a muscle-specific manner under control of the transcription factor MEF2. To explore its functions in vivo, we created a mouse model of Klhl31 loss of function using the CRISPR-Cas9 system. Mice lacking Klhl31 exhibited stunted postnatal skeletal muscle growth, centronuclear myopathy, central cores, Z-disc streaming, and SR dilation. We used proteomics to identify several candidate Klhl31 substrates, including Filamin-C (FlnC). In the Klhl31-knockout mice, FlnC protein levels were highly upregulated with no change in transcription, and we further demonstrated that Klhl31 targets FlnC for ubiquitination and degradation. These findings highlight a role for Klhl31 in the maintenance of skeletal muscle structure and provide insight into the mechanisms underlying congenital myopathies.
AB - Maintenance of muscle structure and function depends on the precise organization of contractile proteins into sarcomeres and coupling of the contractile apparatus to the sarcoplasmic reticulum (SR), which serves as the reservoir for calcium required for contraction. Several members of the Kelch superfamily of proteins, which modulate protein stability as substratespecific adaptors for ubiquitination, have been implicated in sarcomere formation. The Kelch protein Klhl31 is expressed in a muscle-specific manner under control of the transcription factor MEF2. To explore its functions in vivo, we created a mouse model of Klhl31 loss of function using the CRISPR-Cas9 system. Mice lacking Klhl31 exhibited stunted postnatal skeletal muscle growth, centronuclear myopathy, central cores, Z-disc streaming, and SR dilation. We used proteomics to identify several candidate Klhl31 substrates, including Filamin-C (FlnC). In the Klhl31-knockout mice, FlnC protein levels were highly upregulated with no change in transcription, and we further demonstrated that Klhl31 targets FlnC for ubiquitination and degradation. These findings highlight a role for Klhl31 in the maintenance of skeletal muscle structure and provide insight into the mechanisms underlying congenital myopathies.
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U2 - 10.1172/JCI93445
DO - 10.1172/JCI93445
M3 - Article
C2 - 28872460
AN - SCOPUS:85030537924
SN - 0021-9738
VL - 127
SP - 3730
EP - 3740
JO - Journal of Clinical Investigation
JF - Journal of Clinical Investigation
IS - 10
ER -