In Xenopus extracts, replication can be initiated if ORC is removed after it has loaded Cdc6 and MCM proteins.

TLS Online TPP Program

#Id: 8902

#Unit 2. Cellular Organization

Condensins package chromosomes by creating loops by forming intrachromosomal linkages and causes reduction in chromosome length, up to 10,000-fold in vertebrates.

TLS Online TPP Program

#Id: 8903

#Unit 2. Cellular Organization

Chromosome compaction involving progressive chromosome looping:

During prophase, condensin II binds DNA and extrudes large loops

In prometaphase, condensin I forms additional loops nested within the loops formed by condensin II

TLS Online TPP Program

#Id: 8904

#Unit 2. Cellular Organization

TLS Online TPP Program

#Id: 8905

#Unit 2. Cellular Organization

Most of the cohesins along the chromosome arms are removed from chromosomes during prophase, mediated by phosphorylation of cohesins by Plk1 & Aurora B kinase.

TLS Online TPP Program

#Id: 8906

#Unit 2. Cellular Organization

TLS Online TPP Program

#Id: 8907

#Unit 2. Cellular Organization

Centromere associated cohesins are specifically protected from phosphorylation dependent removal by protein phosphatase 2A