. Author manuscript; available in PMC: 2013 Jan 10.

Published in final edited form as: Biochemistry. 2011 Dec 20;51(1):214–224. doi: 10.1021/bi201707v

Table 2.

Phosphorylation sites identified in 5–HT₄R from transgenic mice by LC-MS/MS^a.

Sequence	Mass difference	Phosphorylation sites

AGASSESRPQSADQHSTHR C-III loop	+ 1 phosphate	S²³⁵, S²⁴²
	+ 2 phosphates	S²³⁵ and S²⁴²
	+ 3 phosphates	S²³⁵, S²⁴²and S²³⁶ S²³⁵, S²⁴² and S²⁴⁷ or T²⁴⁸
	+ 4 phosphates	S²³⁵, S²⁴², S²³⁶and S²³⁸ S²³⁵, S²⁴², S²³⁶ and S²⁴⁷ or T²⁴⁸

RPSILGQTVPCSTTTINGSTHVLR C-terminus	+ 1 phosphate	S³³⁸
	+ 2 phosphates	S³³⁸ and S³⁵⁴ or T³⁵⁵
	+ 3 phosphates	S³³⁸ and other 2-4 residues among T²⁴³, S²⁴⁷, T²⁴⁸, T²⁴⁹, T²⁵⁰, T²⁵¹, S³⁵⁴ and T³⁵⁵
	+ 4 phosphates
	+ 5 phosphates

This analysis was performed as described in Experimental Procedures.