Even juvenile leaves of tobacco exhibit programmed cell death

Abstract

Although the relationship between leaf senescence and programmed cell death (PCD) has been actively researched, no research had been carried out previously on juvenile and young leaves. We showed evidence of PCD (DNA laddering by agarose gel electrophoresis and DNA fragmentation by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assays) for juvenile and young leaves of Nicotiana tabacum. Additionally, confocal laser scanning microscopy of nuclei in protoplasts from juvenile leaves clarified the beginning stages of nuclear fragmentation. We concluded that even juvenile leaves of tobacco exhibit PCD and that tobacco leaves grow while undergoing PCD from the initial stages of development until senescence.