= Noriko Ueki
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<Noriko Ueki> investigates how swimming green algae respond to <light>. A 2016 study led by Ueki examined <Chlamydomonas reinhardtii> mutants lacking a normal <eyespot> and found that their direction of <phototaxis> could reverse relative to normal cells under the same chemical conditions. The result made the optical arrangement of the <biological cell> part of the explanation for its behavior.<Eyespot-dependent determination of the phototactic sign in Chlamydomonas reinhardtii by Noriko Ueki and others>[abstract; Figures 2 and 4]{ref}
The <carotenoid> layers of an <eyespot> help control which direction of illumination reaches light-sensitive <channelrhodopsins>. Without that shielding, the cell body can act as a <convex lens>, concentrating <light> arriving from the rear. The investigators demonstrated the lens effect by imaging a small letter through the cells with a <microscope>. This is an illuminating example of a physical structure changing the meaning of a sensory signal: the same light-sensitive machinery can receive its strongest illumination from a different direction. Comparing mutants, a rescued strain and normal cells connected the optical effect with the observed <phototaxis>.<Eyespot-dependent determination of the phototactic sign in Chlamydomonas reinhardtii by Noriko Ueki and others>[Figures 2, 4 and 5; proposed interpretation in Figure 6]{ref}
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