Expression of SHOOT MERISTEMLESS, WUSCHEL, and ASYMMETRIC LEAVES1 Homologs in the Shoots of Podostemaceae: Implications for the Evolution of Novel Shoot Organogenesis[W]

  title={Expression of SHOOT MERISTEMLESS, WUSCHEL, and ASYMMETRIC LEAVES1 Homologs in the Shoots of Podostemaceae: Implications for the Evolution of Novel Shoot Organogenesis[W]},
  author={Natsu Katayama and Satoshi Koi and Masahiro Kato},
  journal={Plant Cell},
  pages={2131 - 2140}
This work explores how organogenesis of the shoot apical meristem (SAM)-less shoots evolved from that of the typical SAM-mediated shoots in the aquatic eudicot Podostemaceae. Based on the expression patterns of STM, WUS, and ARP orthologs, the leaf in SAM-less shoot species is initiated as a SAM and differentiates into a single apical leaf, resulting in the evolution of novel shoot-leaf mixed organs in Podostemaceae. Podostemaceae (the river weeds) are ecologically and morphologically unusual… 

Figures from this paper

Gene expression analysis of aquatic angiosperms podostemaceae to gain insight into the evolution of their enigmatic morphology.
A gene expression analysis found that the SAM-less Podostemoideae leaf has mixed identity of SAM and leaf, and provided insight into the evolution of the shoot in Podostemaceae.
Comparative anatomy of embryogenesis in three species of Podostemaceae and evolution of the loss of embryonic shoot and root meristems
It is inferred that the conventional embryonic shoot meristem was lost in Podostemaceae via two steps, that is, the loss of a distinct L1 layer and the Loss of the OC, whereas the lost of the embryonic root meristems occurred once by misspecification of the hypophysis.
Origin and development of the cryptic shoot meristem in Zeylanidium lichenoides (Podostemaceae).
ZlSTM expression demonstrated that the meristematic identity is partly retained in the embryonic shoot apex of Z. lichenoides and how it is involved in plumular leaf development in the seedling is determined.
Molecular bases for phyllomorph development in a one-leaf plant, Monophyllaea glabra.
It is postulate that the GM is required for growth of a phyllomorph by providing undifferentiated cells and/or growth regulators to the BM and/ or PM.
Modification and co-option of leaf developmental programs for the acquisition of flat structures in monocots: unifacial leaves in Juncus and cladodes in Asparagus
Recent findings in evo-devo studies are highlighted, especially on Juncus unifacial leaves and Asparagus cladodes, which are leaf-like organs at the axils of scale leaves, which discuss how flat structures have evolved and morphologically diversified in shoot systems of monocot species.
Floral anatomy and vegetative development in Ceratophyllum demersum: a morphological picture of an "unsolved" plant.
The initiation pattern of organs in the outer whorls of C. demersum flowers is distorted by mechanical pressure, resulting in the phyllotactic variation of staminate flowers.
Cladodes, leaf-like organs in Asparagus, show the significance of co-option of pre-existing genetic regulatory circuit for morphological diversity of plants
The results indicated that the co-option and alteration of pre-existing GRC play an important role in acquisition and subsequent morphological diversification of A. asparagoides.
Isolation, expression and evolution of FERTILIZATION INDEPENDENT ENDOSPERM homologs in Podostemaceae
This work reports the isolation, characterization and expression patterns of homologs of Fertilization Independent Endosperm (FIE) in two species of Podostemaceae, Zeylanidium olivaceum and Polypleurum stylosum, and suggests that in the absence of double fertilization and endosperm the expression of FIS complex genes perhaps is obliterated in PodostEMaceae.
Gene expression analysis on enigmatic shoots in Podostemaceae
Summary: Podostemaceae (riverweeds) is a family of aquatic angiosperms growing on rocks under running water. The plants evolved unique body plans such as root-borne shoots for adaptation to such an
Cladodes, leaf-like organs in asparagus, show the significance of co-option of pre-existing genetic regulatory circuit for morphological diversity of plants
Results indicated that the co-option and alteration of pre-existing G rC play an important role in acquisition and subsequent morphological diversification, and suggested that only a part of the GrC involved in leaf development appears to have been co-opted into cladode development.


Endogenous Leaf Initiation in the Apical‐Meristemless Shoot of Cladopus queenslandicus (Podostemaceae) and Implications for Evolution of Shoot Morphology
Comparison in the presence or absence of a shoot apical meristem, cell separation, and tissue splitting in Podostemaceae shows that this organogenetic pattern may be a defining evolutionary novelty of the Asian‐Australian lineage of the subfamily Podostemoideae.
Developmental morphology of the shoot in Weddellina squamulosa and implications for shoot evolution in the Podostemaceae.
Weddellinoideae, like Tristichoideae), have a shoot apicalMeristem, leading to the hypothesis that the meristem was lost in Podostemoideae and that the shoot apicals disappeared in the early evolution of Podostemaceae.
Initiation of axillary and floral meristems in Arabidopsis.
The formation of axillaryMeristems and floral meristems in Arabidopsis is described by monitoring the expression of the SHOOT MERISTEMLESS and AINTEGUMENTA genes and it is hypothesized that the STM-negative region that develops on the flanks of the inflorescence meristem is a bract primordium and that the floralMeristem proper develops in the "axil" of this bractPrimordium.
The WUSCHEL gene is required for shoot and floral meristem integrity in Arabidopsis.
The results suggest that the WUS gene is specifically required for central meristem identity of shoot and floral meristems to maintain their structural and functional integrity.
Leaf development in the absence of a shoot apical meristem in Zeylanidium subulatum (Podostemaceae).
The developmental anatomy of the shoot of Zeylanidium subulatum borne on the prostrate root attached to submerged rock surfaces is investigated to find innovations occur in some Podostemaceae that have become increasingly adapted to extreme aquatic habitats.
Developmental anatomy of the reproductive shoot in Hydrobryum japonicum (Podostemaceae)
Bract development, like vegetative leaf development, is unique to this podostemad, while floral-organ development is conserved.
Development of the floral shoot and pre-anthesis cleistogamy in Hydrobryopsis sessilis (Podostemaceae)
The Indian Podostemoideae appear to show a shift from xenogamy or geitonogamy either in a chasmogamous flower to complete autogamy in a cleistogamous plant, indicating a trend towards cryptic self-fertilization.
The Role of KNOX Genes in the Evolution of Morphological Novelty in Streptocarpusw⃞
P phylogenetic analysis suggested a gene duplication before the subgeneric split of Streptocarpus and resolved species relationships, supporting multiple evolutionary origins of the rosulate and unifoliate morphologies.
Heterotopic expression of MPF2 is the key to the evolution of the Chinese lantern of Physalis, a morphological novelty in Solanaceae.
  • Chaoying He, H. Saedler
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2005
The effects of heterotopic expression of MPF2 in floral tissues is involved in two novel traits: expression of the ICS and control of male fertility, underline the importance of recruitment of preexisting transcription factors in the evolution of novel floral traits.
Mechanisms that control knox gene expression in the Arabidopsis shoot.
It is suggested that AS1 and AS2 promote leaf differentiation through repression of knox expression in leaves, and that SE and PKL globally restrict the competence to respond to genes that promote morphogenesis.