FIGURE 6.

Illustration of alterations in the syndecan-4^–/– mice. (A) The syndecan-4^–/– mice had reduced body weight, muscle weight, muscle fibers and expression of myogenic regulatory transcription factors. (B) The syndecan-4^–/– muscle had increased mRNA levels of syndecan-2 and the ECM components decorin, fibromodulin, biglycan, collagen 1, collagen 3 and the collagen cross-linking enzyme lysyl oxidase (LOX). However, fibromodulin, biglycan and LOX were reduced at the protein level (denoted with star), suggesting that these ECM components are more susceptible to degradation or less efficiently translated when syndecan-4 is absent. The syndecan-4^–/– muscle had also increased activation of the (C) Akt/mTOR/S6K1 and (D) Cleaved Notch1-HES-1 pathways.