Reproduction Abstracts

Chromosomes must be properly segregated during meiosis to transmit the correct set of the parental genome into gametes. Incorrect chromosome segregation produces aneuploid gametes, fertilization of which results in pregnancy loss and congenital diseases such as Down syndrome. However, it is known that the frequency incorrect chromosome segregation is extremely high at meiosis I in oocytes (20–40% in humans), compared to other cell divisions. Moreover, the frequency of the...

Introduction: The large, compact oocyte nucleoli, sometimes referred to as nucleolus precursor bodies (NPBs), are essential for embryonic development in mammals. It has been convincingly documented that zygotes inherit the oocyte nucleolar material and form NPBs again in pronuclei. During early embryonic development, the compact zygote NPBs gradually transform into reticulated nucleoli of somatic cells type. Here we show that zygote NPBs are not required for embryonic and full...