Speaker
Description
Miniaturisation, or an extreme reduction in body size, is present in both the plant and animal
kingdoms. This process has been associated with novel morphological innovations and
functional adaptations. Whilst miniaturisation has been studied in a wide variety of animal
lineages, we lack an understanding of the morphological changes associated with miniaturisation
in plants. The Araceae exhibit a striking evolutionary breadth, encompassing both the smallest
flowering plants and some of the largest herbaceous species known, making it an ideal family with
which to explore the concept of miniaturisation. We focused on duckweeds, investigating the
morphogenesis and homology of their fronds with those of other Aroids. Duckweeds measure just
a few millimetres. Their aerial body plan consists of a single frond or thallus, which divides
asexually through clonal reproduction. We followed morphogenesis in Lemna minor fronds and
observed that cell division was tightly constrained to a narrow time window during early
organogenesis, suggesting that the early cessation of division constrains final frond size.
Transcriptional dissection of the duckweed frond revealed that it comprised distinct zones with
homology to either leaves or petioles in Aroids, suggesting that the duckweed frond is a hybrid
organ consisting of a fused stem and leaf. Collectively, our data support the hypothesis that while,
in animal lineages such as tardigrades, miniaturisation has arisen through the loss of body plan
components, in duckweeds, it has arisen through a restriction in cell division and fusion, rather
than the loss of organs.
Keywords
Developmental Biology; Transcriptomics; Imaging
| Corresponding author email | anthony.bishopp@nottingham.ac.uk |
|---|---|
| Scientific Session | Cell Biology, Physiology, Metabolisms |
