Biochemical variation of Phyllodactylus unctus and P. paucituberculatus

A survey of 27 gene products of presumptive isozyme gene loci has been used to determine the systematic status of a population identified as Phyllodactylus unctus in Michoacan, Mexico; it is determined that this population should be placed in cynonomy with P. paucituberculatus. The genetic distance estimate predicts a divergence time from P. unctus of baja california of 16 million yr (esterases not considered) to 18 million yr (esterases included), which correlates with geological dates for the formation of the cape region of baja california and genetic distance estimates for two other trasgulfian reptilian sister groups. Isozyme variability is low and heterozygosity estimates yield intermediate values between those of fossorial and low vagility lizards and those of sit-and-wait predator lizards.     

THE EFFECT OF GIBBERELLIC ACID ON THE ABSORPTION AND TRANSLOCATION OF PHOSPHORUS-32 BY BEAN PLANTS

Linck , A. J., and Theodore W. Sudia . (U. Minnesota, St. Paul.) The effect of gibberellic acid on the absorption and translocation of phosphorus-32 by bean plants. Amer. Jour. Bot. 47(2) : 101—105. Illus. 1960.–Plants of Phaseolus vulgaris, variety ‘Black Valentine,‘ treated with 1 p.p.m. gibberellic acid supplied to the roots for 4 hr. were compared with nontreated. plants for phosphorus-32 uptake. Plants treated with gibberellic acid where transpiration was either rapid or restricted absorbed more phosphorus-32 than those not treated. More phosphorus-32 was recovered from plants free to transpire than from plants in high humidity. In plants free to transpire, significantly more phosphorus was present in the treated plants after 28 hr. and significantly more phosphorus-32 accumulated in treated plants in those parts actively growing, i.e., stem apex, second internode and first trifoliate leaf, and in the roots. For plants in high humidity atmosphere significantly more phosphorus-32 was absorbed by the treated plants at the end of 4 hr. than in the non-treated plants and this difference was maintained throughout all times of harvest. For plants in high humidity atmosphere, significantly more phosphorus-32 accumulated in the lower portions, i.e., roots, hypocotyl, first internode and primary leaves, of treated plants than of non-treated plants, while the differences for the second internode, the first trifoliate leaf and the stem apex were not significant between treated and non-treated plants.     

Reversible Inhibition of Fusion Activity of a Paramyxovirus Fusion Protein by an Engineered Disulfide Bond in the Membrane-Proximal External Region

Cysteines were introduced into the membrane-proximal external region (MPER) of the paramyxovirus F protein. A disulfide bond formed, and the mutant protein was expressed at the cell surface but was fusion inactive. Reduction of the disulfide bond restored fusion activity. The data indicate that in addition to dissociation of the three-helix bundle stalk domain of prefusion F, the MPER region also needs to separate for F to be able to refold and cause fusion.     

New species of Podandrogyne (Cleomaceae) I. Two species from western Colombia and eastern Panama

Podandrogyne chocoensis and Podandrogyne caucana, two new species of Cleomaceae from western Colombia and eastern Panama, are described and illustrated. In view of their probable relationship to each other, but somewhat isolated position with respect to the majority of species of Podandrogyne, the new subsection Breviracemosae is proposed.