Centriole duplication involves the growing of a procentriole (progeny centriole) next to the proximal end of each pre-existing centriole (parental centriole). The molecular mechanisms that regulate procentriole elongation remain obscure. We show here that expression of the centriolar protein CPAP (centrosomal P4.1-associated protein) is carefully regulated during the cell cycle, with the protein being degraded in late mitosis. Depletion of CPAP inhibited centrosome duplication, whereas excess CPAP induced the formation of elongated procentriole-like structures (PLSs), which contain stable microtubules and several centriolar proteins. Ultrastructural analysis revealed that these structures are similar to procentrioles with elongated microtubules. Overexpression of a CPAP mutant (CPAP-377EE) that does not bind to tubulin dimers significantly inhibited the formation of CPAP-induced PLSs. Together, these results suggest that CPAP is a new regulator of centriole length and its intrinsic tubulin-dimer binding activity is required for procentriole elongation.

Decellularization is the process by which cells are discharged from tissues/organs, but all of the essential cues for cell preservation and homeostasis are retained in a three-dimensional structure of the organ and its extracellular matrix components. During tissue decellularization, maintenance of the native ultrastructure and composition of the extracellular matrix (ECM) is extremely acceptable. For recellularization, the scaffold/matrix is seeded with cells, the final goal being to form a practical organ. In this review, we focus on the biological properties of the ECM that remains when a variety of decellularization methods are used, comparing recellularization technologies, including bioreactor expansion for perfusion-based bioartificial organs, and we discuss cell sources. In the future, decellularization-recellularization procedures may solve the problem of organ assembly on demand.

In mammals, the two main types of adipose tissues, white and brown adipose tissues, exert different physiological functions. White adipose tissue (WAT) is for storing energy, while brown adipose tissue (BAT) is for energy consumption. Adipose-derived stem cells (ADSCs) are abundant in WAT and BAT, have multipotent characteristics, and are easily extracted. ADSCs can be differentiated into several cell lineages, including adipocytes, osteoblasts, chondrocytes (cartilage cells), myocytes, and neuronal cells. Therefore, ADSC could be considered as a strategy for future regenerative medicine and tissue engineering.