Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
Lia Heinemann-Yerushalmi
Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
Sharon Krief
Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
Ruth Adler
Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
Bareket Dassa
Bioinformatics Unit, Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
Dena Leshkowitz
Bioinformatics Unit, Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
Minchul Kim
Developmental Biology/Signal Transduction, Max Delbrueck Center for Molecular Medicine, Berlin, Germany; Team of syncytial cell biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
Guy Bewick
Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
The proprioceptive system is essential for the control of coordinated movement, posture, and skeletal integrity. The sense of proprioception is produced in the brain using peripheral sensory input from receptors such as the muscle spindle, which detects changes in the length of skeletal muscles. Despite its importance, the molecular composition of the muscle spindle is largely unknown. In this study, we generated comprehensive transcriptomic and proteomic datasets of the entire muscle spindle isolated from the murine deep masseter muscle. We then associated differentially expressed genes with the various tissues composing the spindle using bioinformatic analysis. Immunostaining verified these predictions, thus establishing new markers for the different spindle tissues. Utilizing these markers, we identified the differentiation stages the spindle capsule cells undergo during development. Together, these findings provide comprehensive molecular characterization of the intact spindle as well as new tools to study its development and function in health and disease.