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DNA TOPOLOGY:  Regulation & Biological Implications

 

The double helical shape of DNA has become a popular icon nowadays. This topology has deep implications for the genome biology.

  • Since DNA molecules are extremely long, they are packaged into chromatin fibers by a hierarchy of micro- and macro- topological domains. Yet, the DNA double helix needs to unfold and unwind during gene transcription and chromosome replication. Therefore, intracellular DNA undergoes severe topological constraints.

  • A ubiquitous class of enzymes, termed topoisomerases, reduces DNA topological problems by producing transient DNA breaks and passing DNA strands throughout each other. Numerous antibiotics and anti-cancer drugs kill cells by interfering the activity of topoisomerases.

  • The topological state of DNA has broad effects on all genome transactions and vice versa. A complex interplay between chromatin architecture (epigenomes) with the activity of topoisomerases and other motor activities (polymerases, helicases, remodellers, SMCs) determines where DNA twisting and coling forces need to be generated or dissipated, and which DNA entanglements must be preserved or eliminated.

Over the past three decades, I investigated the occurrence of DNA supercoils, knots and catenanes across eukaryotic chromosomes; as well as the molecular mechanisms that generate, stabilize and dissolve them.

 

Joaquim Roca 
Molecular Biology Institute of Barcelona (IBMB)
Baldiri Reixac 10, 08028 Barcelona, Spain

joaquim.roca@ibmb.csic.es
j.roca@csic.es

>>> ACADEMIC TRACK
     PAST RESEARCH  &  CURRENT PROJECTS        A glimpse on  DNA TOPOLOGY  &  TOPOISOMERASES

Mechanism of Type-2 Topoisomerases

Type-2 DNA Transport Preferences

Type-2 Inhibition

DNA Torsional Stress at Chromatin

DNA KNOTS as 3D footprints

TOPOLOMICS

Methds & Approaches

Reviews & Comments

Basic Notions (Lk, Tw, Wr)

Vocabulary

Electrophoresis

Type-1A

Type-1B

Type-2A

Type-2B

Topo Nomenclator

     
 

 

 

 

Web-page  created  by  J Roca   2016