350px|right|thumb|Microtubule dynamics during preprophase and prophase in plant cell mitosis, modified from Donukshe et al. The images follow a Tobacco BY-2 cells|tobacco BY-2 cell through the first stages of mitosis (c. 12 minutes). The growing ends of microtubules are shown in green (labeled with [[green fluorescent protein fused to the microtubule plus end binding protein EB1 of Arabidopsis thaliana). N = Nucleus, V = Vacuole, PPB = Preprophase band, MTN = Microtubule nucleation starts at the nuclear envelope, NEB = Nuclear envelope breakdown at the onset of prometaphase. Also see the movie
350px|right|thumb|Microtubule dynamics during preprophase and prophase in plant cell mitosis, modified from Donukshe et al. The images follow a Tobacco BY-2 cells|tobacco BY-2 cell through the first stages of mitosis (c. 12 minutes). The growing ends of microtubules are shown in green (labeled with [[green fluorescent protein fused to the microtubule plus end binding protein EB1 of Arabidopsis thaliana). N = Nucleus, V = Vacuole, PPB = Preprophase band, MTN = Microtubule nucleation starts at the nuclear envelope, NEB = Nuclear envelope breakdown at the onset of prometaphase. Also see the movie corresponding to this figure.]]
Preprophase is an additional phase during mitosis in plant cells that does not occur in other eukaryotes such as animals or fungi. It precedes prophase and is characterized by two distinct events: The formation of the preprophase band, a dense microtubule ring underneath the plasma membrane. The initiation of microtubule nucleation at the nuclear envelope.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).