10         20         30         40         50         60
         |          |          |          |          |          |
MLGWVQRVLP QPPGTPQKTK QEEEGTEPEP ELEPKPETAP EETELEEVSL PPEEPCVGKE - 60
VAAVTLGPQG TQETALTPPT SLQAQVSVAP EAHSSPRGWV LTWLRKGVEK VVPQPAHSSR - 120
PSQNIAAGLE SPDQQAGAQI LGQCGTGGSD EPSEPSRAED PGPGPWLLRW FEQNLEKMLP - 180
QPPKISEGWR DEPTDAALGP EPPGPALEIK PMLQAQESPS LPAPGPPEPE EEPIPEPQPT - 240
IQASSLPPPQ DSARLMAWIL HRLEMALPQP VIRGKGGEQE SDAPVTCDVQ TISILPGEQE - 300
ESHLILEEVD PHWEEDEHQE GSTSTSPRTS EAAPADEEKG EVVEQTPREL PRIQEEKEDE - 360
EEEKEDGEEE EEEGREKEEE EGEEKEEEEG REKEEEEGEK KEEEGREKEE EEGGEKEDEE - 420
GREKEEEEGR GKEEEEGGEK EEEEGRGKEE VEGREEEEDE EEEQDHSVLL DSYLVPQSEE - 480
DQSEESETQD QSEVGGAQTQ GEVGGAQALS EESETQDQSE VGGAQDQSEV GGAQAQGEVG - 540
GAQEQDGVGG AQDQSTSHQE LQEEALADSS GGSFQMSPFE ALQECEALKR

The outer segment of vertebrate photoreceptors hosts all the signaling components required for visual transduction. Specific to rod photoreceptors is a set of three glutamic acid-rich proteins (GARPs) as follows: two soluble forms, GARP1 and GARP2, and the N-terminal cytoplasmic domain (GARP' part) of the B1 subunit of the cyclic GMP-gated channel. GARPs have been shown to interact with proteins at the rim of the disc membrane. The function of GARP proteins is linked to their structural disorder. They may provide flexible spacers or linkers tethering the cyclic GMP-gated channel in the plasma membrane to peripherin at the disc rim to produce a stack of rings of these protein complexes along the long axis of the outer segment. GARP proteins could provide the environment needed for protein interactions in the rim region of discs. Subunit of cyclic nucleotide-gated (CNG) channels, nonselective cation channels, which play important roles in both visual and olfactory signal transduction. When associated with CNGA1, it is involved in the regulation of ion flow into the rod photoreceptor outer segment (ROS), in response to light-induced alteration of the levels of intracellular cGMP.