Endoreductie

Endoreductie is a term in Dutch biology that refers to endoreduplication, the process by which a cell duplicates its genome without undergoing cytokinesis, resulting in polyploid cells with increased DNA content. It can occur by repeated rounds of DNA synthesis without mitosis (endoreduplication) or by mitosis with incomplete cytokinesis (endomitosis).

This phenomenon is common in plants and in certain animal tissues. In plants, endoreduplication is frequent in leaf mesophyll, developing fruit, and seed tissues, contributing to cell enlargement and higher metabolic capacity. In animals, megakaryocytes in bone marrow undergo endomitosis to generate polyploid cells used in platelet production. Endoreduction is typically tissue- and context-specific, and is regulated by developmental and environmental factors.

Functions and consequences include increased cell size, enhanced biosynthetic capacity, and altered gene expression, enabling rapid tissue growth or accumulation of storage compounds. Regulation involves cell cycle controls, including cyclin-dependent kinases and their inhibitors; in plants, regulators such as SIAMESE-related inhibitors help shift cells from complete mitosis to endoreduplication, while hormones and stress cues can influence the process.

Detection and study rely on measuring DNA content, typically by flow cytometry, and examining nuclear size and DNA labeling to identify polyploid cells.

See also: endoreduplication, polyploidy, endomitosis, cell cycle.