Detection and measurement of abnormal posture under stressful conditions in age-related mutants

Matsuda, Sakiyo*; Nitta, Nazuki*; Tamura, Miku*; 鈴木 芳代; 坂下 哲哉; 石井 直明*; 簗瀬 澄乃*

no journal, , 

Oxidative stress threatens cellular constructs including lipids, proteins and nucleic acids. As a result, oxidative stress causes or influence apoptosis, degenerative diseases and aging. Recently, we found an abnormal posture in short-lived mutants such as and , exposed to hyperoxia. In this study, we detected the hyperoxia-induced abnormal posture in and mutants compared with wild-type N and long-lived strains. 4-day-old animals placed on a NGM agar plate with a fixed bacterial lawn were exposed to hyperoxia (90% of oxygen) overnight. After the exposure, some animals were immediately recorded as digital images with up to 400-fold magnification of the microscope. The images were analyzed using image-processing software by a previously published method. To evaluate the posture of the body, we introduced a novel standard, namely the "posture index" as the absolute average of the relative angle between adjacent dividing points. As a result of this investigation, we can not only intuitively but also quantitatively and statistically understand a tendency of the behavior in various postural responses under stressful conditions in the short-lived mutants.