Intermolecular recombination of herpes simplex virus type 1 (HSV-1) was studied by analysing the segregation of strain-specific restriction enzyme cleavage sites among progeny viruses produced after co-infection by two HSV-1 strains differing in eight restriction enzyme cleavage sites. Out of 93 progeny viruses examined, 51 clones were recombinant, and crossover sites of the recombinants were m...

17Beta-estradiol (E2) acts through the estrogen receptor (ER) to regulate uterine epithelial cell growth, proliferation, differentiation, and secretory protein production. We have previously shown that E2-induced uterine epithelial proliferation is mediated indirectly by ER alpha-positive stroma; epithelial ER alpha is neither necessary nor sufficient for E2-induced uterine epithelial mitogenes...

Epithelia from lung rudiments in which secondary bronchial buds are already established (14th and 13th gestational day for rat and mouse respectively) are able to undergo branching morphogenesis and cytodifferentiation in submandibular mesenchyme in vitro, whereas lung epithelium from one day younger foetuses rarely gives a morphogenetic response to submandibular mesenchyme and usually differen...

UNLABELLED Recombination plays a critical role in virus evolution. It helps avoid genetic decline and creates novel phenotypes. This promotes survival, and genome sequencing suggests that recombination has facilitated the evolution of human pathogens, including orthopoxviruses such as variola virus. Recombination can also be used to map genes, but although recombinant poxviruses are easily prod...

In this issue, reveal that different meiotic recombination mechanisms predominate in fission yeast and budding yeast. Budding yeast usually form crossover recombinants through double Holliday junctions, whereas fission yeast unexpectedly appear to form crossover recombinants through single junctions.

Hepatitis C virus (HCV) is an important human pathogen infecting hepatocytes. With the advent of infectious cell culture systems, the HCV particle assembly and release processes are finally being uncovered. The HCV core and NS5A proteins co-localize on cytoplasmic lipid droplets (cLDs) or on the endoplasmic reticulum (ER) at different stages of particle assembly. Current knowledge on assembly a...

Nearly all cases of Hepatitis B virus (HBV) infections in South Korea have the C2 genotype. Here, we have identified a chronically infected patient who was co-infected with HBV of both the A2 and C2 genotypes by screening 135 Korean chronically infected patients using direct sequencing protocols targeting the 1032-bp polymerase reverse transcriptase (RT) region. Further polymerase chain reactio...

Recombinants of preexisting human immunodeficiency virus type 1 (HIV-1) strains are now circulating globally. To increase our understanding of the importance of these recombinants, we assessed recombination within an individual infected from a single source by studying the linkage patterns of the auxiliary genes of HIV-1 subtype B. Maximum-likelihood phylogenetic techniques revealed evidence fo...

Electrophoretic polymorphisms for stomach alcohol dehydrogenase (ADH-C2) and kidney L-alpha-hydroxyacid oxidase (HAOX-B4) have been identified in an Asian subspecies of mouse, Musmusculus castaneous. These variants are inherited in a normal Mendelian fashion with two alleles in each case showing codominant expression. The structural gene loci for those enzymes (Adh-3 and Hao-2, respectively) ar...