Loss of PICH Results in Chromosomal Instability, p53 Activation, and Embryonic Lethality

Area of Science:

• Cell Biology
• Genetics
• Developmental Biology

Background:

• PICH (Polo-like kinase interacting coiled-coil protein) is a DNA translocase.
• It plays a vital role in resolving anaphase DNA bridges and ensuring accurate chromosome segregation.

Purpose of the Study:

• To investigate the physiological relevance of PICH by creating a PICH-deficient (KO) mouse model.
• To understand the consequences of PICH deficiency on embryonic development and cellular processes.

Main Methods:

• Generation of Pich KO mice.
• Analysis of embryonic development, DNA damage, chromosomal instability, p53 activation, and apoptosis in KO embryos.
• Assessment of mouse embryonic fibroblasts (MEFs) for chromosomal instability and transformation potential.

Main Results:

• Pich KO mice exhibit embryonic lethality due to global DNA damage accumulation.
• KO embryos show chromosomal instability, p53 activation, and increased apoptosis but survive until E12.5.
• Absence of p53 does not rescue the viability of Pich KO embryos.
• Pich-deficient MEFs display chromosomal instability and resistance to oncogenic transformation.

Conclusions:

• PICH is essential for maintaining chromosomal integrity in rapidly proliferating cells.
• PICH plays a critical role during embryonic development and is implicated in tumorigenesis.