Activation of Nucleases, PCD, and Mobilization of Reserves in the Araucaria angustifolia Megagametophyte During Germination

MOYANO, LAURA; FAVRE, LEONARDO C.; LÓPEZ-FERNÁNDEZ, MARÍA P.; RODRÍGUEZ, FLORENCIA S.; FAVRE, LEONARDO C.; MOYANO, LAURA; RODRÍGUEZ, FLORENCIA S.; LÓPEZ-FERNÁNDEZ, MARÍA P.; CORREA, MARÍA D.; MALDONADO, SARA; CORREA, MARÍA D.; MALDONADO, SARA

INFORMATION SYSTEMS FRONTIERS

Frontiers Media S.A

Año: 2018 vol. 9 p. 1 - 13

1664-462X

The megagametophyte of mature seeds of Araucaria angustifolia consists of cells withthin walls, one or more nuclei, a central vacuole storing proteins, and a cytoplasm richin amyloplasts, mitochondria and lipid bodies. In this study, we describe the process ofmobilization of reserves and analyzed the dismantling of the tissue during germination,using a range of well-established markers of programmed cell death (PCD), including:morphological changes in nuclei and amyloplasts, DNA degradation, and changes innuclease profiles. TUNEL reaction and DNA electrophoresis demonstrate that DNAfragmentation in nuclei occurs at early stages of germination, which correlates withinduction of specific nucleases. The results of the present study add knowledge on thedismantling of the megagametophyte of genus Araucaria, a storage tissue that storesstarch as the main reserve substance, as well as on the PCD pathway, by revealingnew insights into the role of nucleases and the expression patterns of putative nucleasegenes during germination.