S100A1: A Regulator of Striated Muscle Sarcoplasmic Reticulum Ca²⁺ Handling, Sarcomeric, and Mitochondrial Function

Figure 1

Schematic depiction of the secondary structure of an S100 protein. The monomeric structure consists of a repetitive EF-hand motif, whereas eachCa²⁺-binding Loop (Loop I and II) is flanked by 𝛼-helices. The N-terminal and the C-terminal EF hands are connected by a linker region (hinge region). The hinge region and the C-terminal extension (boxed in red) display the least amount of sequence homology among S100 paralogs. Reproduced with modifications from Donato [5]. [http://www.ncbi.nlm.nih.gov/pubmed/11390274?itool= EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum&ordinalpos=9].