Formal proof of the requirement of MESP1 and MESP2 in mesoderm specification and their transcriptional control via specific enhancers in mice.

MESP1 and MESP2 are transcriptional factors involved in mesoderm specification, somite boundary formation and somite polarity regulation. However, Mesp quadruple mutant zebrafish displayed only abnormal somite polarity without mesoderm specification defects. In order to re-evaluate Mesp1/Mesp2 mutants in mice, Mesp1 and Mesp2 single knockouts (KOs), and a Mesp1/Mesp2 double KO were established using genome-editing techniques without introducing selection markers commonly used before.

Disruption of genetic interaction between two autosomal regions and the X chromosome causes reproductive isolation between mouse strains derived from different subspecies.

Reproductive isolation that initiates speciation is likely caused by incompatibility among multiple loci in organisms belonging to genetically diverging populations. Laboratory C57BL/6J mice, which predominantly originated from Mus musculus domesticus, and a MSM/Ms strain derived from Japanese wild mice (M. m.

Hybrid breakdown caused by substitution of the X chromosome between two mouse subspecies.

Hybrid breakdown is a type of reproductive failure that appears after the F2 generation of crosses between different species or subspecies. It is caused by incompatibility between interacting genes. Genetic analysis of hybrid breakdown, particularly in higher animals, has been hampered by its complex nature (i.