The giant axolotl genome uncovers the evolution, scaling, and transcriptional control of complex gene loci
Siegfried Schloissnig, Akane Kawaguchi, Sergej Nowoshilow, Francisco José Calazans Falcón, Leo Otsuki, Pietro Tardivo, Nataliya Timoshevskaya, Melissa C. Keinath, Jeramiah J. Smith, S. Randal Voss, Elly M. Tanaka
Abstract
Significance The axolotl is an important model organism because it is a tetrapod with a similar body plan to humans. Unlike humans, the axolotl regenerates limbs and other complex tissues. Therefore, the axolotl contributes to understanding evolution, development, and regeneration. With sophisticated tools for gene modification and tissue labeling, a fully assembled genome sequence was a sorely missing resource. Assembly was difficult because the genome size is 10× that of humans. Here, we use a cross-linking strategy called Hi-C to link together fragmented genome sequences to chromosome scale. We show that gene regulation occurs over very large genomic distances and that mitotic chromosomes are packaged efficiently.