A cyclin-binding motif in human papillomavirus type 18 (HPV18) E1^E4 is necessary for association with CDK–cyclin complexes and G2/M cell cycle arrest of keratinocytes, but is not required for differentiation-dependent viral genome amplification or L1 capsid protein expression

Investigation into the effects the HPV E4 protein has in viral life cycleThe G2/M arrest function of human papillomavirus (HPV) E4 proteins is hypothesized to be necessary for viral genome amplification. Full-length HPV18 E1^E4 protein is essential for efficient viral genome amplification. Here we identify key determinants within a CDK-bipartite consensus recognition motif in HPV18 E1^E4 that are critical for association with active CDK–cyclin complexes and in vitro phosphorylation at the predicted CDK phosphorylation site (threonine 23). The optimal cyclin-binding sequence (43RRLL46) within this E4 motif is required for G2/M arrest of primary keratinocytes and correlates with cytoplasmic retention of cyclin B1, but not cyclin A. Disruption of this motif in the E4 ORF of HPV18 genomes, and the subsequent generation of stable cell lines in primary keratinocytes revealed that this motif was not essential for viral genome amplification or L1 capsid protein induction. We conclude that the HPV18 E4 G2/M arrest function does not play a role in early vegetative events

Grouping Practices and Reading Outcomes for Students with Disabilities

This meta-analytic review investigated the relationship between reading outcomes for students with disabilities (learning disabilities, behavior disorders) and the grouping formats (student pairs, small groups, combinations of different formats) used during their reading instruction. Twenty studies produced between 1975 and 1995 met criteria for inclusion in the meta-analysis. Results indicated positive effects for alternative grouping formats compared to whole class instruction; support for the efficacy of student pairing was particularly strong. In addition, analyses indicated that outcomes for students involved in cross-age tutoring varied significantly by students' role (tutor vs. tutee) within the pair. Implications of the findings are discussed with regard to classroom practice in the teaching of reading to students with disabilities. </jats:p

Instructional Grouping for Reading for Students with LD Implications for Practice

Teachers' grouping practices during reading instruction can serve as a critical component in facilitating effective implementation of reading instruction and inclusion of students with disabilities in general education classes. In this article, we provide an overview of the recent research on grouping practices (whole class, small group, pairs, one-on-one) during reading instruction for students with disabilities. After discussion of each grouping format, implications for practice are highlighted with particular emphasis on instructional practices that promote effective grouping to meet the needs of all students during reading in general education classrooms