From genome to function: the Arabidopsis aquaporins

Table 3 Protein sizes and characteristics of Arabidopsis AQPs

	PIP	Amino acid	TIP	Amino acid	NIP	Amino acid	SIP	Amino acid
1	AtPIP1;1*	286	AtTIP1;1	251	AtNIP1;1*†	296	AtSIP1;1	240
2	AtPIP1;2*	286	AtTIP1;2	253	AtNIP1;2†	294	AtSIP1;2	243
3	AtPIP1;3*	286	AtTIP1;3	252	AtNIP2;1-pseudo	139	AtSIP2;1	237
4	AtPIP1;4*	287	AtTIP2;1	250	AtNIP2;1†	288
5	AtPIP1;5*	287	AtTIP2;2	250	AtNIP3;1†	323
6	AtPIP2;1*	287	AtTIP2;3	250	AtNIP3;1-pseudo	262
7	AtPIP2;2*	285	AtTIP2;x-pseudo	124	AtNIP4;1†	283
8	AtPIP2;3*	285	AtTIP3;1	268	AtNIP4;2†	283
9	AtPIP2;4*	291	AtTIP3;2	267	AtNIP5;1†	304
10	AtPIP2;5*	286	AtTIP4;1	249	AtNIP6;1*†¶	305
11	AtPIP2;6*	289	AtTIP5;1*¶	256	AtNIP7;1†	275
12	AtPIP2;7*	281
13	AtPIP2;8*	278

The three putative pseudogenes, or possible 'short' AQPs, are depicted in their subfamilies. *Amino-terminal extensions (longer than approximately 10 amino acids amino-terminal of TM1). †Carboxy-terminal extensions (more than approximately 10 amino acids carboxy-terminal of TM6). ¶AQP with amino-terminal extensions that satisfy, at least superficially (that is, predicted by some programs) criteria for protein transport into mitochondria. No experimental evidence, however, exists for this conjecture. Putative signal sequences for chloroplast import could not be identified.

ISSN: 1474-760X