PEPTIDES RELATED TO TELEOSTEI FISH GROWTH HORMONE RELEASING FACTOR

摘要

The invention provides peptides which are potent in stimulating the release of pituitary GH in fish and amphibians which have a substantial portion or all of the following sequence: R1-R2-R3-R4-R5-Phe-R7-R8-R9-Tyr-Arg-R12-R13-Leu-R15-Gln-LeuR18-Ala-Arg -Lys-R22-L eu-R24-R25-R26-R27-R28-R29-R30-R31-Gly-R33-R34-R35-R36-R-37R-38R-39R-4 0R-41-R42- R43-R44-Ser wherein R1 is N-Me Tyr, Tyr, desNH2-Tyr, D-Tyr, N-Et Tyr, N-Ip Tyr, N-Me His, His, desNH2-His, D-His, N-Et His, and N-Ip His; R2 is Ala, D-Ala or D-NMA; R3 is Asp or D-Asp; R4 is Gly or Ala; R5 and R27 are selected from the group consisting of Met, Leu, Val, Nva, Gln, Thr, Ile, Ala, Arg, Asn, Asp, Cys, Glu, Gly, His, Nle, Lys, Phe, Pro, Ser, Tyr and Trp; R7 is Asn or Thr; R8 is Lys, Asn or Ser; R9 is Ala or Ser; R12 is Lys or Arg; R13 is Ala, Val or Ile; R15 is Gly or Ala; R18 is Ser or Tyr; R22 is Tyr or Leu; R24 is His or Gln; R25 is Thr, Asp, or Glu; R26 is Leu or Ile; R28 is Ala, Ser or Asn; R29 is Lys or Arg; R30 is Arg or Gln; R31 is Val or Gln; R33 is Gly or Glu; R34 is Gly, Arg or Ser; R35 is Ser or Asn; R36 is Met, Leu, Val, Nva, Gln, Thr, Ile or Nle; R37 is Ile or Glu; R38 is Glu, Gln or Arg; R39 is Asp, Arg or Gly; R40 is Asp, Ser or Ala; R41 is Asn, Arg or Lys; R42 is Glu, Phe, Ala or Val; R43 is Pro, Asn or Arg; R44 is Leu or Ala; provided however that at least one of the following is present: R7 is Asn, R8 is Lys, R13 is Ala, R22 is Tyr and R25 is Thr; and provided further that any or all of the residues after R27 may be deleted. A 29-residue peptide beginning at the N-terminus may be preferred. These peptides, as well as their nontoxic salts, are considered to be particularly useful in agriculture.