Mitosis Course

Lesson 1 • Cell Cycle Overview and Phases

Maps G1, S, G2, and M phases and their functional boundaries. Positions mitosis within the broader context of cell proliferation.

Lesson 2 • The Cytoskeleton and Motor Proteins

Introduces microtubules, actin filaments, and intermediate filaments. Establishes how motor proteins generate force critical to chromosome movement.

Lesson 3 • Eukaryotic Cell Architecture Overview

Covers organelle identity, membrane systems, and compartmentalisation. Provides the structural vocabulary needed for all subsequent mitosis content.

Lesson 4 • Chromatin and Chromosome Structure

Examines DNA packaging from nucleosomes to condensed chromosomes. Links chromatin organisation to gene regulation and mitotic fidelity.

Lesson 1 • Replication Fidelity and Proofreading

Examines polymerase proofreading and mismatch repair pathways. Establishes why low error rates are essential for faithful chromosome segregation.

Lesson 2 • Replisome Assembly and Elongation

Details the replisome components that synthesise leading and lagging strands. Explains how coordinated synthesis ensures complete chromosome duplication.

Lesson 3 • Replication Origin Selection and Licensing

Covers origin recognition complexes and the licensing model that prevents re-replication. Connects origin control to genome stability entering mitosis.

Lesson 4 • Telomere Replication and End Protection

Addresses the end-replication problem and telomerase-mediated solutions. Links telomere integrity to chromosome stability in dividing cells.

Lesson 1 • Nuclear Envelope Breakdown Preparation

Covers CDK1-mediated lamina phosphorylation and NPC disassembly that precede open mitosis. Bridges G2 biochemistry to prophase structural changes.

Lesson 2 • Cyclin B–CDK1 Activation Cascade

Traces cyclin B accumulation and CDK1 activation through Cdc25 phosphatase. Establishes the biochemical switch that triggers mitotic entry.

Lesson 3 • Centrosome Duplication and Maturation

Describes centriole duplication during S phase and PCM expansion in G2. Links centrosome number control to bipolar spindle formation.

Lesson 4 • DNA Damage Checkpoint in G2

Covers ATM and ATR signalling that halts mitotic entry after DNA damage. Connects checkpoint fidelity to prevention of chromosomal aberrations.

Lesson 1 • Chromosome Condensation in Prophase

Details condensin-driven loop extrusion and the resulting chromosome morphology. Establishes how compaction enables accurate segregation.

Lesson 2 • Mitotic Spindle Assembly Pathways

Compares centrosome-driven, chromatin-driven, and augmin-mediated spindle assembly. Shows how multiple pathways ensure robust bipolar spindle formation.

Lesson 3 • Kinetochore Structure and Composition

Describes the inner and outer kinetochore layers and their microtubule-binding modules. Grounds students in the molecular architecture of chromosome attachment.

Lesson 4 • Aurora B and Error Correction

Covers Aurora B kinase activity in destabilising incorrect attachments. Establishes the tension-sensing model that ensures amphitelic attachment.

Lesson 1 • APC/C Activation and Substrate Order

Describes APC/C-Cdc20 activation and the ordered degradation of securin and cyclin B. Links substrate timing to irreversible anaphase commitment.

Lesson 2 • Chromosome Congression Mechanisms

Explains polar ejection forces, kinetochore motors, and arm-length effects on alignment. Connects biophysical forces to metaphase plate formation.

Lesson 3 • Checkpoint Silencing and Satisfaction

Covers p31comet, TRIP13, and dynein-mediated stripping that silence the checkpoint. Shows how full attachment triggers anaphase onset.

Lesson 4 • Spindle Assembly Checkpoint Signaling

Details MCC assembly at unattached kinetochores and APC/C inhibition. Establishes the molecular logic of the wait-anaphase signal.

Lesson 1 • Telophase Nuclear Envelope Reformation

Covers CDK1 inactivation, lamin reassembly, and ER-derived membrane sealing around chromosomes. Links mitotic exit signalling to nuclear reformation.

Lesson 2 • Cohesin Cleavage and Anaphase Onset

Details separase activation, cohesin cleavage, and the resulting sister chromatid separation. Establishes the molecular trigger for chromosome segregation.

Lesson 3 • Anaphase B Spindle Elongation

Explains antiparallel microtubule sliding by kinesin-5 and cortical pulling forces. Shows how spindle elongation increases pole-to-pole distance.

Lesson 4 • Contractile Ring Assembly and Constriction

Describes RhoA activation, actin-myosin ring formation, and progressive constriction. Connects central spindle signals to cleavage furrow positioning.

Lesson 1 • Aurora Kinase Family Functions

Compares Aurora A and Aurora B substrates, localisation, and regulatory roles. Connects kinase activity to spindle assembly and chromosome segregation fidelity.

Lesson 2 • Polo-like Kinase 1 Regulatory Network

Examines PLK1 substrate targeting, polo-box domain function, and its roles across mitotic stages. Establishes PLK1 as a master mitotic coordinator.

Lesson 3 • Mitotic Exit Network and CDK Inactivation

Covers the mitotic exit network, phosphatase reactivation, and ordered CDK substrate dephosphorylation. Links exit signalling to successful cytokinesis.

Lesson 4 • Feedback Loops Ensuring Mitotic Fidelity

Analyses positive and negative feedback loops that create bistable mitotic transitions. Shows how feedback prevents partial or premature mitotic exit.

Lesson 1 • Mitotic Defects in Cancer Biology

Examines checkpoint gene mutations, oncogene-driven mitotic stress, and CIN in tumour evolution. Establishes mitotic dysfunction as a driver of cancer progression.

Lesson 2 • Centrosome Amplification and Multipolar Spindles

Explains how extra centrosomes arise and how cells cluster them to survive. Connects centrosome amplification to elevated missegregation risk.

Lesson 3 • Mechanisms of Chromosome Missegregation

Catalogues merotelic attachments, cohesion fatigue, and premature separation as missegregation causes. Grounds students in the origins of aneuploidy.

Lesson 4 • Therapeutic Targeting of Mitotic Regulators

Surveys antimitotic drug classes, their mechanisms, and resistance pathways. Connects mitotic biology to clinical strategies for proliferating cell diseases.