Fig. 1.
Cx37 is phosphorylated at S319 in Rin cells with arrested growth consequent to induced Cx37 expression. (A) Spectra of a peptide extending from S319 to K329 with b and y ion fragments identified. (B) Table of predicted fragment masses for the parent ion with sequence shown in amino acid (AA) column. The observed b-fragment (N-terminal) and y-fragment (C-terminal) ions, which are highlighted in blue or yellow, allowed unambiguous localization of the phosphorylation event at S319. The masses of all fragments containing S319, B1-11 and Y11, include the mass of a phosphate group (95 Da); in contrast, the mass of all fragments that do not include S319 (Y1-10) do not include the mass of a phosphate group, which indicates that only S319 is phosphorylated. pS319 was identified in 204 of 559 fragments (Jacobsen et al., 2019).