Table 4. Sequence diversity and distribution of naturally occurring vasopressin-like nonapeptides.

Peptide	Sequence‡	Organism(s)	Ref.§
Vasopressin	CYFQNCPRG*	Eutherian mammals	P01185
Lysopressin	CYFQNCPKG*	Marsupials and pigs	P01183
Phenypressin	CFFQNCPRG*	Marsupials	0909223B¶
Vasotocin	CFITNCPPG* CFVRNCPPG* CFISDCARG*	Daphnia pulex Platynereis dumerilii Saccoglossus kowalevskii	E9H8T6 A6YIC5 D1LXH6
Ile4-vasotocin	CYIINCPRG*	Branchiostoma floridae	[23]
Conopressin#	CFIRNCPP*	Conus textile	P86255
γ-conopressin vil#	CLIQDCPEG*	Conus villepinii	P85141
[Arg]-conopressin S#	CIIRNCPRG*	Conus striatus	P05487
[Lys]-conopressin G	CFIRNCPKG*	Leeches and molluscs	P05486
Conopressin T#	CYIQNCLRV*	Conus tulipa	[15]
Inotocin	CLITNCPRG* CLIVNCPRG*	Arthropods, ants Camponotus floridanus	A3RE83 [2]
Vasotocin (ancestral)††	CYIQNCPRG*	Nonmammalian vertebrates	P69129

^†Relative frequency sequence logo plot, conserved cysteine residues are highlighted in yellow, hydrophobic, aromatic and non-polar amino acids are labeled in gray, negatively charged residues are labeled in blue and positively charged residues are labeled in red. All sequences are amidated at the C-terminus, as indicated by the asterisk.

^‡Conserved cysteine residues forming a disulfide bond are highlighted in bold. All sequences are amidated at the C-terminus, as indicated by the asterisk.

^§UniProtKB entry, unless otherwise stated.

^¶GenBank protein accession number.

^#Peptides from Conus spp. have been isolated from venom ducts, glutamic acid represents γ-carboxyglutamate.

^††Presumed ancestral oxytocin/vasopressin nonapeptide [2].