PURPOSE To determine the size variation of the X-chromosomal human red and green visual pigment gene array in the general population using pulsed field gel electrophoresis and Southern blotting. METHODS Peripheral blood lymphocytes were prepared from 67 anonymous males. The cells were embedded in agarose and the genomic DNA digested with restriction enzyme Not I. The resulting DNA fragments w...

When integumentary tissue pigments are contained in chromatophores, tissue color might not depend exclusively on the amount of pigment. Whether coloration does or does not reflect pigment concentration may be very significant for intraspecific communication, for example when pigment concentration provides fitness-related information. We studied the pigment responsible for the orange/red ventral...

Our ability to see in bright light depends critically on the rapid rate at which cone photoreceptors detect and adapt to changes in illumination. This is achieved, in part, by their rapid response termination. In this study, we investigate the hypothesis that this rapid termination of the response in red cones is dependent on interactions between the 9-methyl group of retinal and red cone opsin...

Kinetin induces formation of red pigment in seedlings of Amaranthus retroflexus in the dark. This effect is similar to the light-induced formation of pigment. Light and kinetin do not act in a simple additive way. The pigment is not an anthocyanin, and its formation is not affected by inhibitors of anthocyanin formation.

The compound eye of the butterfly Papilio xuthus consists of three different types of ommatidia, each containing nine photoreceptor cells (R1-R9). We have found previously that the R5-R8 photoreceptors of type II ommatidia coexpress two different mRNAs, encoding opsins of green- and orange-red-absorbing visual pigments (Kitamoto et al., 1998). Do these cells contain two functionally distinct vi...

In Paper XXXIV of this series (1) we described the isolation of a pigment from the ether-soluble constituents obtained on saponification of the acetone-soluble fat. The present report deals with the determination of the chemical constitution of the pigment. In order to indicate its origin, we propose to designat,e the pigment by the name phthiocol. Phthiocol crystallizes in yellow prisms which ...

From Xenorhabdus luminescens XE-87.3 four variants were isolated. One, which produced a red pigment and antibiotics, was luminescent, and could take up dye from culture media, was considered the primary form (XE-red). A pink-pigmented variant (XE-pink) differed from the primary form only in pigmentation and uptake of dye. Of the two other variants, one produced a yellow pigment and fewer antibi...

Precarthamin, a yellow precursor of carthamin, was efficiently isolated from the yellow petals of safflower (Carthamus tinctorius L. ) with Sephadex LH-20 column chromatography and preparative HPLC, and identified with UV-vis and NMR spectrometry. The UV-vis spectrum of precarthamin showed lambda(max) of 238 and 406 nm in MeOH. The molar extinction coefficients of precarthamin at 406 nm in MeOH...

It is desirable in many studies to be able to rapidly measure rates of erythrocyte and hemoglobin destruction. Labeling techniques have been utilized for this purpose but have the disadvantage of requiring several days' to weeks to obtain the desired data plus the hazards of radioactive isotopes. Estimations of hemoglobin turnover from measurements of fecal bile pigment or serum bilirubin conce...

Skin color is determined by epidermal melanin content, the function of which remains poorly understood. Clinically, there is a lower incidence of melanoma in individuals with high levels of constitutive brown/black pigment and/or acquired pigmentation (i.e. tanning). Conversely, individuals with red hair, blue eyes, and inability to tan are at higher risk for developing melanoma. Therefore, pig...