Acentrosomal Spindle Formation Through The Heroic Age Of Microscopy Past Techniques, Present Thoughts, And Future Directions

Spindle bipolarity occurs in plant cells without the presence of animal-like centrosomes. A question still unanswered is what structures contribute to acentrosomal spindle formation in the absence of these organizing centers. Past and present research techniques have highlighted several mitotic structures (i.e., the preprophase band, perinuclear microtubules, and bridge microtubules) and interactions between these structures that appear to be involved in a plant-specific mechanism of establishing spindle bipolarity and organization. In this review, we explore how the discoveries of different microscopy techniques combine to form an emerging hypothesis in plant acentrosomal spindle formation and how this mechanism reflects the importance of organizing cell divisions in a tissue-specific context, based on proper cell wall placement, a hallmark of proper plant development.