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1.
Mol Reprod Dev ; 49(2): 196-202, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9444662

RESUMO

The possible role of tyrosine kinase in the regulation of fowl sperm motility was investigated by using a stable analogue of erbstatin, methyl 2,5-dihydroxycinnamate (2,5-MeC), a specific inhibitor of tyrosine kinase. This inhibited the motility of intact spermatozoa at 30 degrees C in a dose-dependent manner. In contrast, the motility of demembranated spermatozoa was not inhibited by the same concentrations of 2,5-MeC. At 40 degrees C, both intact and demembranated spermatozoa were almost immotile with or without 2,5-MeC. Additionally, intact spermatozoa, stimulated by the addition of Ca2+ or calyculin A, a specific inhibitor of protein phosphatases, lost their motility with the subsequent addition of 2,5-MeC at 40 degrees C. However, unlike the motility, the ATP concentrations of spermatozoa were maintained in about 30-35 nmol ATP/10(9) cells during these incubation periods. The activity of tyrosine kinase of spermatozoa at 30 degrees C, estimated by measuring the phosphorylation of a synthetic peptide substrate, RR-SRC, was 0.17 pmol/min per milligram of protein. This activity was lower than that of fowl testes or chick brain but higher than that of chick liver. These results suggest that tyrosine kinase activity, which is not retained in the axoneme and/or accessory cytoskeletal components, may be involved in the maintenance of flagellar movement of fowl spermatozoa at 30 degrees C.


Assuntos
Trifosfato de Adenosina/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia , Animais , Membrana Celular/fisiologia , Galinhas , Cinamatos/farmacologia , Ativação Enzimática , Masculino , Especificidade de Órgãos , Proteínas Tirosina Quinases/metabolismo , Espermatozoides/metabolismo , Espermatozoides/fisiologia
2.
Biochem Biophys Res Commun ; 240(1): 116-21, 1997 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-9367894

RESUMO

The motility of demembranated fowl spermatozoa was vigorous at 30 degrees C, but decreased markedly following the addition of mitogen-activated protein (MAP) kinase or p34cdc2 kinase substrate peptide. Dephosphorylation of approximately 116, 86 and 79-kDa proteins of demembranated spermatozoa was observed after the addition of MAP kinase or p34cdc2 kinase substrate peptide. The activities of MAP kinase and histone H1 kinase of spermatozoa, estimated by measuring the phosphorylation of myelin basic protein and histone H1 as substrates, were 1.22 and 0.29 pmol/min/ mg protein, respectively. Both enzymatic activities of spermatozoa were lower than those of chick brain, but higher than those of chick liver. These results suggest that the phosphorylation of axonemal and/or accessory cytoskeletal proteins mediated by MAP kinase and p34cdc2 kinase may be involved in the regulation of flagellar movement of fowl spermatozoa.


Assuntos
Proteína Quinase CDC2/farmacologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/farmacologia , Oligopeptídeos/farmacologia , Imobilizantes dos Espermatozoides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Membrana Celular/fisiologia , Galinhas , Masculino , Fosforilação , Proteínas Quinases/metabolismo , Cauda do Espermatozoide/efeitos dos fármacos , Cauda do Espermatozoide/enzimologia , Espermatozoides/fisiologia , Especificidade por Substrato
3.
DNA Res ; 3(2): 95-9, 1996 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-8804862

RESUMO

We present a detailed picture of the disposition of the histone genes in the chicken genome and an almost complete set of the core histone protein sequences. Thirty-nine histone genes, six H1, nine H2A, eight H2B, eight H3 and eight H4, were located within a histone gene cluster of 110 kb, which was covered by five cosmid clones and two lambda clones. Results of our sequence analyses, together with those reported previously, generated a set of the core histone amino acid sequences as follows: three H2A variants, four H2B variants, two H3 variants and an H4 protein.


Assuntos
Galinhas/genética , Histonas/química , Histonas/genética , Sequência de Aminoácidos , Animais , Mapeamento Cromossômico , Clonagem Molecular , Família Multigênica , Fases de Leitura Aberta , Mapeamento por Restrição , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
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