Temperature-induced hand inversion inBacillus subtilis macrofibers

Cellular and Molecular Life Sciences -     

Genetic localization of a mutation rendering the growth of E coli K12 insensitive to illumination at 365 nm]

The genotype of the Nop mutant recently isolated from the E. coli K 12 strain AB 1157 has been characterized. This mutant lacks 4-thiouridine in its tRNA and is much less susceptible to near ultraviolet-induced growth delay than wild type cells. This phenotype results from a single mutation called nuv which has been localized on the E. coli genetic map. nuv is found by conjugation to lie between the origins of injection of Hfr P4X and Hfr cavalli in the vicinity of the lac gene. Cotrans-duction with bacteriophage P1 more precisely maps nuv at 0.3 min. clockwise from tsx.     

Induction of cutaneous or subcutaneous fibroblastic tumors in the Afghan pika (Ochotona rufescens rufescens) by injection or bovine papilloma virus]

Newborn Afghan pikas have been inoculated with bovine papilloma virus via the subcutaneous route. Cutaneous or subcutaneous fibromas and fibrosarcomas were observed after a mean incubation period of nine months. The transmission of these tumors by homograft has been obtained. Bovine papilloma virus antibodies have been demonstrated in most of the animals inoculated at birth. They have not been detected in animals bearing transplanted tumors.     

4-Thiouridine and photoprotection in Escherichia coli K 12]

A high level of protection is observed in the Escherichia coli K 12 strain AB 1157 rec A 1 nuv+ whose transfer RNA contains 4-thiouridine. In contrast, the photoprotection level is low and observed at higher doses in a strain which differs from the former by a single mutation, nuv-, (lack of 4-thiouridine). This nucleoside is therefore an important chromophore leading to photoprotection. This conclusion is corroborated by the similarity of the action spectra for 8-13 link formation in tRNA and for photoprotection.     

Mutations in two adjacent novel genes are associated with epidermodysplasia verruciformis

Epidermodysplasia verruciformis (OMIM 226400) is a rare autosomal recessive genodermatosis associated with a high risk of skin carcinoma that results from an abnormal susceptibility to infection by specific human papillomaviruses (HPVs). We recently mapped a susceptibility locus for epidermodysplasia verruciformis (EV1) to chromosome 17q25. Here we report the identification of nonsense mutations in two adjacent novel genes, EVER1 and EVER2, that are associated with the disease. The gene products EVER1 and EVER2 have features of integral membrane proteins and are localized in the endoplasmic reticulum.