In the previous article we introduced two concepts in sémiotique to be used in the area of comparative physiology and biochemistry; synchronie and diachronie. The former describes a snapshot of a complex biological system taken at a certain time point, whereas the latter describes the dynamic aspect of a complex biological system through time. In order to achieve the latter it is necessary to study the time-dependent change of system parameters such as kinetics of protein expression. We have established a methodology to trace the dynamic aspect of protein expression for as many as several hundred proteins and called it “proteomic trajectory mapping.” In this follow-up review we will explain proteomic trajectory mapping in detail which is essential for studying the diachronic aspect of living things.

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In the present review, we summarize the mechanisms of motor program selection of the wind-evoked behavios in the cricket Gryllus bimaculatus. In response to the air current stimulus, crickets initiate flying when they are suspended in air, but they initiate walking when they are on the ground. They initiate swimming to the same stimulus when they are placed on the water surface. The legs of the cricket are equipped with many chemosensory hairs and some of them contain water receptors. Among three pairs of legs, fore-legs bear the largest number of water receptors. The receptors mainly locate on the surface of the tibia and tarsus of legs, and are likely to be responsible for the initiation of swimming and for the inhibition of flying. Motor program selection between swimming and walking is also investigated by placing crickets on the surface of methylcellulose (MC) solution with different viscosities. Higher viscosity of MC solution resulted in a lower relative occurrence of swimming. In contrast, lower viscosity of MC solution resulted in a higher relative occurrence of walking. The results suggest that resistance force from the substrate to the legs seem to be important to elicit walking. The air current stimulus evokes flying after bilateral dissection of the connectives between the suboesophageal and prothoracic ganglia even when the operated cricket is placed on the water surface. We identified four types of “swimming initiating neurons” in the suboesophageal ganglion physiologically and morphologically. These findings suggest that particular neurons in the cricket CNS play important roles in the selection of wind-evoked behaviors.

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  Diadromous fish, which are species that migrate between fresh and salt water, usually have paired visual pigments; rhodopsin and porphyropsin. In order to investigate the changes in rhodopsin-porphyropsin ratio in chum and pink salmon in relation to the change in their habitat, the ratios were analyzed in individual fish prior to stocking, during the sea run. The ratio decreased after upstream river migration. Moreover, in the sea, the rhodopsin-porphyropsin ratio of chum salmon was always slightly higher than that of pink salmon. The largest difference in the individual variation was observed in individuals caught with a set net placed near the mouth of a home river. Based on the above results, the following factors are discussed with respect to evaluation of salmon resources: stocking time, indication of change in habitation, rate of local stock, and difference in swimming depth.
  The optomotor reaction, which is movements undertaken by an animal to stabilize the image of a moving target, is widely used to assess the vision of animals. Here the optomotor reaction was used to measure the spectral sensitivity and polarized light vision of juveniles of three salmonid fish. Masu salmon were very sensitive at 400 nm, suggesting that these fish are sensitive to ultraviolet light (UV). Moreover, masu salmon were able to follow optomotor stimuli composed of polarized light, suggesting they are sensitive to the plane of polarisation of illumination.
  This study also shows that salmon fry need to experience light in order to develop retinomotor movements.

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  In general, it is known that the insect egg is very difficult to prepare for transmission electron microscope (TEM). Especially, the one of the most difficult specimen is the mature eggs of silkworm, Bombyx mori. It is important that the chorion was removed gently by the needles before fixation, and the processes of dehydration and substitution were spent thoroughly by the conventional method. These samples could be easy to obtain the ultrathin sections, but there were no structures in the yolk cell cytoplasm which are thought to be an artifact by preparation process. The high-pressure freezing in combination with the freeze substitution methods were examined to observe the ultrastructure of B.mori egg without losing yolk components. Many lipid droplets and glycogen granules were well preserved in the yolk cell cytoplasm. However the ultrastructure of yolk cell cytoplasm in the prefixed egg with chemical fixative before freezing tended to be damaged, compared with that of the non-fixed egg. The ultrastructure of yolk cell cytoplasm may be influenced by chemical fixation. It is demonstrated that the high-pressure freezing in combination with the freeze substitution methods are suitable for the difficult specimens to prepare by the conventional preparation methods for TEM.

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