Molecular cloning of a preprohormone from sea anemonescontaining numerous copies of a metamorphosis-

Antho lwamide ix agg 4 antho lwamide iii arg4ser ala

This preview shows page 3 - 5 out of 5 pages.

Antho-LWamide IX Agg 4 Antho-LWamide III Arg4Ser-Ala-Glu-Ala-Gly-Gln-Pro-Gly-Leu-Trp-Gly-Lys-Arg],i 1 Antho-LWamide III Arglser-Ala-Asp-Ar1-Gly-Gln-Pro-Gly-Leu-Trp-Gly-Lys-Arg I I Antho-LWamide III ArglSer-Ala-Asp-Pro-Leu-Gln-Pro-Gly-Leu-Trp-Gly-Lys-Arg4' 1 Antho-LWamide V Arg>Ser-Ala-Asp-Ala-Arg-Gln-Pro-Gly-Leu-Trp-Gly-Lys-Arg, 1 Antho-LWamide VI Lys2Ser-Pro-Gly-Leu-Trp-Gly-Arg{n 1 Lys -ArgGlu-Leu -Val -Gy-Leu-Trp-G1y- Gy-Lys-Argo 1 Lys-Arg4Glu-Ile-Tyr-Ala-Leu-Trp-Gly-Gly-Lys-ArgiP 1 ArglISer-Ala-Glu-Pro-Pro-Gln-Phe-Glu-Asp-Leu-Glu-Asp-Leu-Lys-Lys -LySq I Sites of initial cleavage at tribasic, dibasic, or monobasic residues are indicated by arrows. MMA copies are underlined and printed in boldface type. Highly likely, but putative, peptide sequences are underlined only. Uncertain mature sequences or residues are underlined by a dashed line. The underlined neuropeptide sequences can be found in Fig. 1 at the following amino acid positions: a, 285, 306, 327, 367, 388, 409, 430, 451; b, 348; c, 76; d, 127, 148, 169, 200, 231, 273, 294, 315, 336, 376, 397, 418, 439, 460; e, 106; f, 85, 252; g, 481; h, 470; i, 97, 118, 139, 160; j, 243; k, 212; 1, 264; m, 181; n, 358; o, 221; p, 190; q, 492. Neurobiology: Leviev and Grimmelikhuijzen
Image of page 3
11650 Neurobiology: Leviev and Grimmelikhuijzen still unclear (see Discussion). Finally, there are other, putative peptide sequences flanked by basic residues, but it is not certain whether these will yield intact peptides (underlined by a dashed line in Table 1) (see Discussion). The amino acid sequence of the Antho-LWamide precursor and its corresponding cDNA show no significant sequence similarly to other amino acid or nucleotide sequences con- tained in the GenBank or EMBL data bases. DISCUSSION We have cloned the precursor protein for the metamorphosis- inducing neuropeptide MMA that has recently been isolated from A. elegantissima by Leitz and coworkers (5, 6). The precursor protein contains 10 copies of authentic, immature MMA (Table 1). Nine of these neuropeptide copies are followed by pairs of basic residues, which are established cleavage sites for endoproteolytic precursor processing (12). One authentic, immature MMA copy (at positions 348-354 of Fig. 1; see also Table 1) is followed by a single basic residue. Processing at single basic residues is also known, and it is especially frequent in certain invertebrate prohormones (7, 12, 14-18). After comparing various prohormones that are cleaved at single basic residues, Devi (14) has proposed several rules that have to be fulfilled in order to obtain cleavage. Many of these requirements are satisfied for the immature MMA copy that is followed by the single basic residue. One important rule, however, says that at position -3, -5, or -7 of the basic residue where cleavage occurs, a second basic residue should be present. This rule is not followed. Nevertheless, we think that the MMA copy at positions 348-354 will be released from its precursor by cleavage at the C-terminal side of its C- terminally4ocated Lys residue. This is for the following rea- sons: (i) the surroundings of this MMA copy is nearly identical to that of the other nine copies of authentic MMA, and it lies in the middle of a
Image of page 4
Image of page 5

Want to read all 5 pages?

You've reached the end of your free preview.

Want to read all 5 pages?

  • Spring '09
  • WAITE
  • Gln Leu Gly Leu Trp Gly Lys Arg Gln Ser Arg Ile Gly Leu Trp Gly Arg Ser Ala, Asp Pro Gln Gln Pro Gly Leu Trp G1Y Lys Arg Gln Asn Pro Gly Leu Trp Gly Arg Ser, Leu Gly Ala Glu Glu Glu Ser Lys Glu Glu Asp Lys Lys Arg Ser Ala Ala

{[ snackBarMessage ]}

Get FREE access by uploading your study materials

Upload your study materials now and get free access to over 25 million documents.

Upload now for FREE access Or pay now for instant access
Christopher Reinemann
"Before using Course Hero my grade was at 78%. By the end of the semester my grade was at 90%. I could not have done it without all the class material I found."
— Christopher R., University of Rhode Island '15, Course Hero Intern

Ask a question for free

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern