Gravitational response of the slime mold Physarum.
Adv Space Res
; 14(8): 21-34, 1994.
Article
em En
| MEDLINE
| ID: mdl-11537920
ABSTRACT
The acellular slime mold Physarum polycephalum is used as a model system to investigate the graviresponse of single cells which possess no receptors specialized for the perception of gravity. To obtain insights into the gravity-signal transduction mechanism the light response of the cell is used Macroplasmodia of the slime mold show clear geo- and phototaxes. Gravity increases and white light decreases transiently the contraction frequency of plasmodial strands whereby both responses follow the same time pattern. Since mitochondria play a major role in changing the contraction rhythm in response to light and gravity stimuli, the simultaneous and subsequent inductions of the opposing light and gravity responses and their mutual influences on one another were investigated. The experiments were performed in weightlessness (0 g)--simulated on the fast-rotating clinostat as well as in actual weightlessness during the IML-1 Space Shuttle mission. The results indicate that mitochondria (chondriome) are part of the acceleration-stimulus reaction chain in Physarum. Two models for a direct gravireceptor mechanism are discussed.
Palavras-chave
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Voo Espacial
/
Ausência de Peso
/
Physarum polycephalum
/
Sensação Gravitacional
/
Gravitação
Limite:
Animals
Idioma:
En
Revista:
Adv Space Res
Assunto da revista:
MEDICINA AEROESPACIAL
Ano de publicação:
1994
Tipo de documento:
Article
País de afiliação:
Alemanha