Table 1.
Sequences and binding affinities of KP-10 and analogs
| Peptide | Sequence | IC50, nM |
|---|---|---|
| KP-10 | YNWNSFGLRF-NH2 | 1.0 + 0.3 |
| Alanine screened analogs | ||
| ANA1 | ANWNSFGLRF-NH2 | 23.2 + 14.3 |
| ANA2 | YAWNSFGLRF-NH2 | 145.1 + 138.0 |
| ANA3 | YNANSFGLRF-NH2 | 2.7 + 0.7 |
| ANA4 | YNWASFGLRF-NH2 | 43.5 + 15.5 |
| ANA5 | YNWNAFGLRF-NH2 | 0.8 + 0.4 |
| ANA6 | YNWNSAGLRF-NH2 | 109.5 + 89.8 |
| ANA7 | YNWNSFALRF-NH2 | 4.6 + 1.5 |
| ANA8 | YNWNSFGARF-NH2 | 77.4 + 10.0 |
| ANA9 | YNWNSFGLAF-NH2 | 42.3 + 6.7 |
| ANA10 | YNWNSFGLRA-NH2 | |
| Amino acid exchange analogs | ||
| ANA11 | FNWNSFGLRF-NH2 | 3.5 + 2.1 |
| ANA12 | YDWNSFGLRF-NH2 | 29.1 + 13.5 |
| ANA13 | YNWDSFGLRF-NH2 | 140.2 + 60.6 |
| ANA14 | YNWNTFGLRF-NH2 | 2.3 + 1.6 |
| ANA15 | YNWNSYGLRF-NH2 | 87.5 + 30.7 |
| ANA16 | YNWNSFGIRF-NH2 | 39.9 + 8.1 |
| ANA17 | YNWNSFGLKF-NH2 | 9.8 + 2.6 |
| ANA18 | YNWNSFGLRH-NH2 | 378.4 + 266.0 |
| Enantiomer exchange analogs | ||
| ANA19 ([dY]1KP-10) | [dY]NWNSFGLRF-NH2 | 3.6 + 0.3 |
| ANA20 | YNWNS[dF]GLRF-NH2 | 252.9 + 144.0 |
| ANA21 | YNWNSFGLR[dF]-NH2 | 447.2 + 173.0 |
IC50 in nM are means ± SE (n = 3–5). KP, kisspeptin; ANA, analog. Binding assays were carried out against [125I]KP-54 binding to KISS1R in CHO-KISS1R membrane preparations. Each receptor binding assay was carried out in triplicate. Changes to the sequence of KP-10 are indicated in bold.