The acquisition of fertilization capacity by sperm is regulated by intracellular pH (pH(i)), but the transport pathways that regulate pH(i) are not well understood. Lishko et al. (2010) now report that Hv1, the voltage-sensitive proton channel, is present in human sperm and is an important regulator of the functional maturation of sperm.

Anyone who’s neglected a houseplant for any length of time knows that plants can’t survive without light. But it’s more complicated than that; in addition to serving as an energy source, light is used by plants as a signal to sense and respond to the environment. For example, both red and blue light send the signal for maturation and flower and seed development. Depriving a plant of such light ...

First described during the 18th century, the cause of night myopia remains a controversial topic. Whereas several explanations have been suggested in the literature, particularly related with accommodation or chromatic shift in scotopic light conditions, no definitive explanation for its aetiology has been provided. We describe an experiment in which ocular refractive state was objectively and ...

-The in vitro chemosensitivity of primary monolayer cultures of human ovarian tumours to a wide range of chemotherapeutic agents has been determined using 3H-leucine incorporation as an index of cytotoxicity. Of 67 specimens received, 35 have been successfully cultured and tested for chemosensitivity. Drugs tested included alkylating agents, antibiotics, antimitotics, antimetabolites and proges...

Light induces the migration of arrestin to the photosensitive membrane in both vertebrate and invertebrate photoreceptors. New work has identified a phosphoinositide lipid binding domain in Drosophila arrestin and implicates PIP(3) in control of arrestin translocation.

Cancer is known for opportunistically utilizing resources from its surroundings for its own growth and survival. In this issue of Cell, Venkatesh et al. demonstrate that this also occurs in the brain, identifying neuronal activity-induced secretion of neuroligin-3 as a novel mechanism promoting glioma proliferation.

hen endothelial cells adhere to the extracellular matrix protein fibronectin, they can proliferate in response to growth factors. Adhesion to laminin, however, brings their cell cycles to a dead stop. Why? Given that the response depends on the composition of the extracellular matrix, Filippo Giancotti and his colleagues at the Memorial Sloan-Kettering Cancer Center (New York, NY) proposed in 1...

Virtually all methods in image processing and computer vision, for removing weather effects from images, assume single scattering of light by particles in the atmosphere. In reality, multiple scattering effects are significant. A common manifestation of multiple scattering is the appearance of glows around light sources in bad weather. Modeling multiple scattering is critical to understanding t...