Aging is an inevitable and fundamental process in nearly all organisms, the process of which is regarded as a passive entropic process of tissue deterioration, and can be characterized by age-related changes. One of the important aspects to describe the process is behavioral changes. C. elegans possesses a number of well-defined and easily measurable behaviors that can be measured with experiments. The behaviors involved in age-related regulation are often associated with many factors, including mutations, drugs, diet, and environmental conditions. Here we offer a number of behavioral measurements and analyses of powerful model system C. elegans to help our customers with aging research.
The pharynx is a neuromuscular organ that undergoes rhythmic contractions in order to facilitate feeding. A maximum pharyngeal pumping rate can be detected in two-day-old adults, and reaches approximately 300 pumps per minute. Usually, pharyngeal pumping undergoes an age-related decline and typically ceases about day 12. Here we provide two measurements of pharyngeal pumping for an individual or a population, including the fast pharyngeal pumping span and the pharyngeal pumping span, involved in an early and a late transition during the decline of pharyngeal pumping. Additionally, these values that are measured can be used to predict lifespan.
Young hermaphrodites display a well-coordinated sinusoidal body movement, and become progressively slower and less coordinated and ultimately ceases altogether as time goes by. Previous studies indicate that C. elegans body movement is connected with several other age-related changes, including lifespan, pharyngeal pumping, and can be affected by the dietary status and environmental temperature. The decline in body movement is positively correlated with the decline in survival probability and can be used to predict lifespan. Besides, the decline in body movement is also positively correlated with the decline in pharyngeal pumping. Furthermore, body movement is likely to be independent of dietary status, and the cold temperature can delay the decline of body movement.
C. elegans has a simple sensory system, consisting of 60 ciliated sensory neurons that a variety of environmental cues such as chemical, thermal and relative position of the body. It is not surprising that the nematodes display progressive, age-related loss of the ability to chemotaxis towards an attractive odorant. The decline in chemotaxis behavior is similar to the decline in spontaneous movement. Isothermal tracking is an experience dependent behavior. The hermaphrodites display an age-related decline in isothermal tracking, and the behavior can be observed until day 15. The age-related decline in isothermal tracking can be accelerated by the activity of insulin/IGF signaling, mitochondrial function and dietary intake.
The defecation motor program (DMP) provides an example of a well-studied rhythmic process, which consists of a stereotyped series of muscular contractions that are coordinated by neural activity. The process of the DMP cycle executes repeatedly with a period of 50-60 seconds, and typically assayed by visual inspection, including the simultaneous contraction of dorsal and ventral posterior body-wall muscles (pBoc), the simultaneous contraction of dorsal and ventral anterior body-wall muscles (aBoc) and the contraction of enteric muscles. Here we provide an automated assay to detect DMP, which is throughput and sensitivity, and is suitable to be performed continuously for arbitrarily long periods, and in highly controlled environments.
|Age-related behavior||Description||Method of measurement||Quantitative|
|Pharyngeal pumping||Test frequency.
Slow pharyngeal pumping: 6-149 pumps per minute (fast pharyngeal pumping span: the time from L4 to the last day of fast pharyngeal pumping)
Fast pharyngeal pumping: >149 pumps/minute (pharyngeal pumping span: the time from L4 to the last day of slow pharyngeal pumping)
|Body movement||Detection frequency and coordination.
Quantification of movement as waves per minute.
Categories of movement ability:
Class A animals: progressing with rhythmic sinusoidal movement,
Class B animals: not active and uncoordinated,
Class C animals: unable to progress but spontaneously move their head or tail and respond to touch
|Chemotaxis||Test response||Dissecting scope||YES|
|Isothermal tracking||Test response||Dissecting scope||YES|
Automated detection of subtle phenotypes and ensure unbiased scoring.
pBocs (dorsal and ventral posterior body-wall muscles)
aBocs (dorsal and ventral anterior body-wall muscles)
|Machine vision approach||YES|
To enable the rapid acquisition of many reliable and useful values, Creative Biogene develops a scalable detection and analysis platform for studying the aspect of age-related behavior. If you are interested in our services, please don't hesitate to contact us for more details.
* For research use only.