Topoisomerase IIalpha (topoIIalpha) and 13S condensin are both required for mitotic chromosome assembly. Here we show that they constitute the two main components of the chromosomal scaffold on histone-depleted chromosomes. The structural stability and chromosomal shape of the scaffolding toward harsh extraction procedures are shown to be mediated by ATP or its nonhydrolyzable analogs, but not ...

This is an experimental study aiming to explore the effect of applying ‘Writing Circles’ strategy (WCs) in writing classrooms. WCs a type collaborative methodology that relies heavily on peer- based learning. The aimed give group not less than 20 students from college languages and translation, Najran University, chance apply circles how it affects their progress writing. It also role scaffoldi...

Molecular dynamics simulation of an atom-resolved bacteriophage P22 capsid model is used to delineate the underlying mechanism of early stage P22 self-assembly. A dimer formed by the C-terminal fragment of scaffolding protein with a new conformation is demonstrated to catalyze capsomer (hexamer and pentamer) aggregation efficiently. Effects of scaffolding protein/coat protein binding patterns a...

The first step in assembly of the bacteriophage P22 is the formation of a T=7 icosahedral "procapsid," the major components of which are the coat protein and an inner core composed of the scaffolding protein. Although not present in the mature virion, the scaffolding protein is required for procapsid assembly. Eleven amino-acid residues at the extreme carboxyl terminus of the scaffolding protei...

Unlike most viral assembly systems, two scaffolding proteins, B and D, mediate bacteriophage øX174 morphogenesis. The external scaffolding protein D is highly ordered in the atomic structure and proper function is very sensitive to mutation. In contrast, the internal scaffolding protein B is relatively unordered and extensive alterations do not eliminate function. Despite this genetic laxity, p...

Bacteriophage P22 serves as a model for the assembly and maturation of other icosahedral double-stranded DNA viruses. P22 coat and scaffolding proteins assemble in vitro into an icosahedral procapsid, which then expands during DNA packaging (maturation). Efficient in vitro assembly makes this system suitable for design and production of monodisperse spherical nanoparticles (diameter approximate...

Microviridae morphogenesis is dependent on two scaffolding proteins, an internal and external species. Both structural and genetic analyses suggest that the COOH-terminus of the internal protein is critical for coat protein recognition and specificity. To test this hypothesis, chimeric internal scaffolding genes between Microviridae members phiX174, G4, and alpha3 were constructed and the prote...

Although filling the gap in reading comprehension gained momentum with the rise of the top-down approach, Vygotsky’ concept of scaffolding and the dual code  theory provided a strong support for the use of paratext to enhance comprehension. Scaffolding is dependent on other-regulation, one type of which is object-regulation. From this vantage-point, various types of paratext can function as sou...

The intentional stance, which has been a conceptual underpinning of much work on multiagent systems, cannot provide an account of coordinated behavior in terms that can apply equally to humans and to agents. We suggest that one must also include social scaffolding in the sense in which “scaffolding” is used by Andy Clark. Critical aspects of the relevant social scaffolding can be formulated in ...