Regulation of the int gene of bacteriophage lambda: activation by the cII and cIII gene products and the role of the Pi and Pl promoters.

The activation of the int gene by the cII and cIII gene products was studied by analysing int expression following infection of UV-irradiated cells by various phage mutants. Residual expression of int, probably from Pl, takes place in the absence of cII/cIII activation. Activation of the int gene, like that of the cI repressor gene, is poor at low multiplicities of infection.

Building a standardized alcoholism interview schedule.

The clinical Alcoholism Interview Schedule (CAIS) is being developed as a standardized instrument for initial assessment of alcoholic patients and as a research tool. Fifty questions cover key areas of clinical concern, and accompanying guidelines describe the method of administration. An initial study of inter-rater reliability has been conducted with five raters independently rating taped interviews with each of ten patients.

Initiation points for DNA replication in nontransformed and simian virus 40-transformed BALB/c 3T3 cells.

The number of initiation points for DNA synthesis per unit length of DNA in rapidly growing cells is greater for simian virus 40-transformed than for nontransformed BALB/c 3T3 cells.

Repressor and int synthesis of bacteriophage lambda in the E. coli host mutant ER437.

Analysis of lambda phage infection of the host mutant ER437 by SDS polyacrylamide gel electrophoresis and autoradiography has revealed altered expression of repressor and integration function (Int). We show that in this host Int as well as repressor synthesis is not dependent upon the lambdacIII gene product in the usual manner, nor is their synthesis turned off in the normal way.

Initiation points for DNA replication in nontransformed and simian virus 40-transformed Chinese hamster lung cells.

Randomly growing Chinese hamster lung cells were pulse-labeled with 3H-thymidine, and the replicating forks of individual DNA fibers were visualized by autoradiography. When grown in complete medium, wild-type SV40-transformed cells had more forks per unit length of DNA than nontransformed cells. In isoleucine-depleted medium, wild-type SV40-transformed cells had fewer forks per unit length than those few nontransformed cells (1-3% of the population) which continued DNA replication.

Towards a typology of relapse: a preliminary report.

This paper outlines an empirical investigation into alcoholic relapse. The model underlying this work hypothesized that relapse in alcoholics is an interaction between (1) situations seen as dangerous in precipitating relapse, (2) the behaviours available within the individuals' repertoire to cope with these situations, (3) the perceived effectiveness of these "coping" behaviours and (4) the degree of alcohol dependence. The results of a "principal components" analysis indicated that "dangerous situations" or relapse precipitants could be categorized as (1) an unpleasant affect, (2) external events and euphoric feelings, (3) social anxiety and (4) lessened cognitive vigilance.

Assembly site of cyanophage LPP-2-SPI in Plectonema boryanum.

Electron microscope studies of infection by the temperature cyanophage SPI show two possible assembly sites within the host Plectonema boryanum: the nucleoplasm and a phage-created space, the "virogenic stroma". Induced prophages appear to develop preferentially in the nucleoplasm.

Analysis of a temperature sensitive mutation in gene cII of bacteriophage lambda.

The mutation cIIts612 was found to map outside the immunity region of phage lambdaimm21 hybrid. As expected of a cII mutation, lambdacIIts612 is unable to stimulate either cI repressor or Int synthesis during the establishment of lysogeny. These results indicate that part of the cII gene of lambda is homologous to that of lambdaimm21 phage.

Efficient suppression of the requirement for N function of bacteriophage lambda by a Rho-defective E.coli suA mutant.

The E. coli suA mutant (T82), which is a suppressor of polarity by virtue of its impaired transcription termination factor (rho) activity, is shown to be an efficient suppressor of lambdaN- mutants. The relief of the N requirement by this host is reflected in a substantial restoration of growth and N-dependent beta-galactosidase expression as well as in a partial relief of polarity of N-defective phages.

A pleiotropic regulatory mutation in lambda bacteriophage.

Lambda bacteriophage mutants, lambdasar, were isolated. These mutants can form plaques on a non lysogenic lawn and are unable to grow on nonimmune (imm-), cro constitutive hosts. Analysis of the restriction of lambdasar by a set of defective lysogens suggested that both the cro and cII gene products participate in the inhibition.