Aurora kinases are highly conserved, essential regulators of cell division. Two Aurora kinase isoforms, A and B (AURKA and AURKB), are expressed ubiquitously in mammals, whereas a third isoform, Aurora C (AURKC), is largely restricted to germ cells. Because AURKC is very similar to AURKB, based on sequence and functional analyses, why germ cells express AURKC is unclear. We report that Aurkc(-/...

Cell division is inherently mechanical, with cell mechanics being a critical determinant governing the cell shape changes that accompany progression through the cell cycle. The mechanical properties of symmetrically dividing mitotic cells have been well characterized, whereas the contribution of cellular mechanics to the strikingly asymmetric divisions of female meiosis is very poorly understoo...

By SATIMARU SENO, MASANOBU MIYAHARA, HIKARU ASAKUBA, OSAMU Oc:HI, KENICHI MATSUOKA AND TAKENORI Toyu t M ACROCYTOSIS has long been recognized as a common occurrence during the development or recovery from acute anemia.1 It was ascribed to the appearance of large numbers of reticulocytes in the peripheral blood. Recently, Brecher and Stohlman demonstrated that the macrocytosis after administrati...

Background: The pregnancy rates from oocytes matured in vitro are much lower than those of in vivo stimulation cycles, indicating that optimization of IVM remains a challenge. Reduced developmental competence of oocytes matured in vitro indicates that current culture systems for oocytes maturation do not adequately support nuclear and/or cytoplasmic maturation. Therefore in this study, we evalu...

Sertoli cells (Sc) are unique somatic cells of testis that are the target of both FSH and testosterone (T) and regulate spermatogenesis. Although Sc of neonatal rat testes are exposed to high levels of FSH and T, robust differentiation of spermatogonial cells becomes conspicuous only after 11-days of postnatal age. We have demonstrated earlier that a developmental switch in terms of hormonal re...

Executioner caspase-3 and -7 are proteases promoting cell death but non-apoptotic roles are being discovered. The heart expresses caspases only during development, suggesting they contribute to the organ maturation process. Therefore, we aimed at identifying novel functions of caspases in heart development. We induced simultaneous deletion of executioner caspase-3 and -7 in the mouse myocardium...

Mammalian oocyte asymmetric division relies on the eccentric positioning of the spindle, resulting in the polar body formation. Small signaling G protein Rac1 is a member of GTPases, which regulates a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases. However, effects of Rac1 on the porcine oocyte maturatio...

Leukemia cells (HL-60) were induced to mature towards granulocytic and monocytic phenotypes using 1.1% dimethyl sulfoxide and 5 X 10(-7) M 1-beta-D-arabinofuranosylcytosine, respectively. Granulocytic maturation was accompanied by a slight decrease in cell volume and in total cell protein, but with an increase in acid phosphatase. DNA histograms showed that after 7 days there was a decrease in ...

A core evolutionary function of the p53 family is to protect the genomic integrity of gametes. However, the role of p73 in the male germ line is unknown. Here, we reveal that TAp73 unexpectedly functions as an adhesion and maturation factor of the seminiferous epithelium orchestrating spermiogenesis. TAp73 knockout (TAp73KO) and p73KO mice, but not ΔNp73KO mice, display a "near-empty seminifero...