海洋生物体发光之潜在机制-凯发k8官网

it has long been known that ¹ blue flashes--a type of bioluminescence--that are visible at night in some ² environments are caused by tiny, unicellular（单细胞的） ³ known as dinoflagellates（鞭毛藻类） . however, a new study has, for the first time, ⁴ the potential ⁵ for this bioluminesence. the study, which was ⁶ funded by the national science foundation, is reported by susan smith of emory school of medicine, thomas decoursey of rush university medical center and colleagues in the oct. 17, 2011 issue of the ⁷ of the national academy of sciences (pnas).

a key aspect of the potential mechanism for bioluminescence in dinoflagellates proposed in the pnas study involves voltage-gated proton channels--channels in ⁹ that can be opened or closed by chemical or electrical events.

j. woodland hastings, a member of the smith and decoursey research team and an author of the pnas article, suggested the presence of voltage-gated proton channels in dinoflagellates almost forty years ago. but the smith and decoursey team only recently confirmed them by the identification and subsequent testing of dinoflagellate ¹⁰ that are similar to genes for voltage-gated proton channels that had ¹¹ been identified in humans, mice and sea squirts（海鞘） .

according to the study, here is how the light-generating process in dinoflagellates may work: as dinoflagellates float, mechanical ¹² generated by the movement of surrounding water sends electrical impulses around an internal ¹³ within the organism, called a vacuole--which holds an abundance of protons. these electrical impulses open so-called voltage-sensitive proton channels that connect the vacuole（胞液） to tiny pockets dotting the vacuole ⁸, known as scintillons.

once opened, the voltage-sensitive proton channels may ¹⁴ protons from the vacuole into the scintillons. protons entering the scintillons then ¹⁵ luciferase--a protein, which produces flashes of light, that is stored in scintillons. flashes of light produced by resulting luciferase ¹⁶ would be most visible during blooms of dinoflagellates.

this research ¹⁷ the novel ^{18 19} a beautiful natural phenomenon in our oceans, and enhances our understanding of dinoflagellates--some of which can produce ²⁰ that are harmful to the environment.