Body weight-dependent troponin T alternative splicing is evolutionarily conserved from insects to mammals and is partially impaired in skeletal muscle of XXXX @entity35 .

@entity28 @entity146 @entity17509 @entity425 @entity35 @entity121 @entity855
Do animals know at a physiological level how much they weigh, and, if so, do they make homeostatic adjustments in response to changes in body weight? Skeletal muscle is a likely tissue for such plasticity, as weight-bearing muscles receive mechanical feedback regarding body weight and consume @entity855 in order to generate forces sufficient to counteract gravity. Using @entity35 , we examined how variation in body weight affected alternative splicing of @entity17509 ( @entity17509 ), a component of the thin filament that regulates the actin-myosin interaction during contraction and modulates force output. In response to normal growth and experimental body weight increases, alternative splicing of @entity17509 in @entity35 gastrocnemius muscle was adjusted in a quantitative fashion. The response depended on weight per se, as externally attached loads had the same effect as an equal change in actual body weight. Examining the association between @entity17509 alternative splicing and @entity855 consumption rate, we found that the @entity17509 splice form profile had a significant association with nocturnal energy expenditure, independently of effects of weight. For a subset of the @entity17509 splice forms, @entity28 Zucker @entity35 failed to make the same adjustments; that is, they did not show the same relationship between body weight and the relative abundance of five @entity17509 b splice forms (i.e. @entity17509 b2-b5 and b8), four of which showed significant effects on nocturnal energy expenditure in @entity35 . Heavier @entity28 Zucker @entity35 displayed certain splice form relative abundances (e.g. @entity17509 b3) characteristic of much lighter, lean animals, resulting in a mismatch between body weight and muscle molecular composition. Consequently, we suggest that body @entity121 @entity17509 expression in @entity28 is a candidate mechanism for @entity425 and @entity146 . Weight-dependent quantitative variation in @entity17509 alternative splicing appears to be an evolutionarily conserved feature of skeletal muscle and provides a quantitative molecular marker to track how an animal perceives and responds to body weight.
