Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: mealworm beetle

Sortuj według:

Ogranicz wyniki do:

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Effects of arginine substitutions on the cardioinhibitory activity of the Led-NPF-I neuropeptide

100%

Marciniak P., Slocinska M., Bednarz P., Grodecki S., Konopinska D., Rosinski G.

Pestycydy

2009

nr 1-4

71-78

Effects of structural changes on the cardioinhibitory activity of the Led-NPF-I peptide (Ala-Arg-Gly-Pro-Gln-Leu-Arg-Leu-Arg-Phe-amide) were examined by replacing Arg residues in positions 2, 7 and 9. Replacement of L-Arg2 with another basic amino acid, such as Lys, His or D-Arg, did not abolish but rather promoted cardioinhibitory activity in giant mealworm beetle Zophobas atratus Fab. Agonistic peptides were also obtained by substitution of Arg residue in position 7 with Lys or D-Arg, and Arg in position 9 with His or D-Arg, respectively. All these analogues showed stronger cardioinhibitory effects than the native peptide at low concentration (10-9 M), and [Lys7]-, [D-Arg7]- and [D-Arg9]-Led-NPF-I also at the higher concentration (10-6 M). However, substitutions of the Arg residues in position 7 with His or in position 9 with Lys caused a loss of the cardioinhibitory activity. In addition, the replacement of Arg residues in all three positions with Lys or Orn caused a reduction of cardioinhibitory activity, although a single substitution of Arg in positions 2 or 7 with Lys yielded agonistic peptides. We conclude that the Arg2 position in the N-terminal region is more tolerant to structural modification than the other two Arg positions located in the C-terminal region.

Vitellogenesis in virgin and mated females of the mealworm beetle, Tenebrio molitor

100%

Michalik J., Chojnicka B., Cymborowski B.

Acta Biochimica Polonica

1996

tom 43

nr 4

A comparison between vitellogenesis in virgin and mated females of Tenebrio molitor showed significant differences at each investigated developmental stage. Yolk protein deposition in oocytes, measured as an increase in their size parameters (length, width, and volume), proceeded much faster and was more efficient in mated females as compared to virgins. In fertilized females the gonadotropic cycle showed a cyclicity with an eight-day period while virgin females finish their vitellogenic stage after the first cycle. These differences were reflected in changes in the rate of protein synthesis in the fat body of females completing vitellogenesis or entering the next oogenetic cycle. In the haemolymph, in addition to a large (158 kDa) and two small (56 kDa and 45 kDa) subunits of vitellogenin, there was an abundance of proteins of 80 kDa and 60 kDa.

Ograniczanie wyników

1 Acta Biochimica Polonica

1 Pestycydy

1 Bednarz P.

1 Chojnicka B.

1 Cymborowski B.

1 Grodecki S.

1 Konopinska D.

1 Marciniak P.

1 Michalik J.

1 Rosinski G.

1 Slocinska M.

1 2009

1 1996

Wyniki wyszukiwania

Effects of arginine substitutions on the cardioinhibitory activity of the Led-NPF-I neuropeptide

Vitellogenesis in virgin and mated females of the mealworm beetle, Tenebrio molitor