Tag: Li L.

Evidence not only for a common origin of all stomata in extant plants but also for relatively simple stomata in the ancestral plant

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不仅为现存植物中所有气孔的共同起源提供证据，而且为祖先植物中相对简单的气孔提供了证据。

Evidência não apenas para uma origem comum de todos os estômatos nas plantas existentes, mas também para estômatos relativamente simples na planta ancestral

Evidencia no solo de un origen común de todos los estomas en las plantas existentes, sino también de estomas relativamente simples en la planta ancestral

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Liverwort bHLH transcription factors and the origin of stomata in plants

Chang G., Ma J., Wang S., Tang M., Zhang B., Ma Y., Li L., Sun G., Dong S., Liu Y., Zhou Y., Hu X., Song C.-P., Huang J. (2023)

Current Biology 33(13): 2806-2813

https://doi.org/10.1016/j.cub.2023.05.050

Highlights

  • •No evidence exists for bHLH Ia gene duplication in the ancestral land plant
  • •The bHLH Ia/IIIb regulatory module is highly conserved in land plants
  • •MpSMF and MpSCRM1/2 affect the development of the epidermis and gametangiophores
  • •MpSMF weakly complements the functions of AtMUTE and AtFAMA

Summary

Stomata are distributed in nearly all major groups of land plants, with the only exception being liverworts. Instead of having stomata on sporophytes, many complex thalloid liverworts possess air pores in their gametophytes. At present, whether stomata in land plants are derived from a common origin remains under debate. 

In Arabidopsis thaliana, a core regulatory module for stomatal development comprises members of the bHLH transcription factor (TF) family, including AtSPCH, AtMUTE, and AtFAMA of subfamily Ia and AtSCRM1/2 of subfamily IIIb. Specifically, AtSPCH, AtMUTE, and AtFAMA each successively form heterodimers with AtSCRM1/2, which in turn regulate the entry, division, and differentiation of stomatal lineages. 

In the moss Physcomitrium patens, two SMF (SPCH, MUTE and FAMA) orthologs have been characterized, one of which is functionally conserved in regulating stomatal development.

We here provide experimental evidence that orthologous bHLH TFs in the liverwort Marchantia polymorpha affect air pore spacing as well as the development of the epidermis and gametangiophores. We found that the bHLH Ia and IIIb heterodimeric module is highly conserved in plants. Genetic complementation experiments showed that liverwort SCRM and SMF genes weakly restored a stomata phenotype in atscrm1, atmute, and atfama mutant backgrounds in A. thaliana. In addition, homologs of stomatal development regulators FLP and MYB88 also exist in liverworts and weakly rescued the stomatal phenotype of atflp/myb88 double mutant. These results provide evidence not only for a common origin of all stomata in extant plants but also for relatively simple stomata in the ancestral plant.

CO2 response in Arabidopsis guard cells

 

A molecular pathway for ​CO2 response in Arabidopsis guard cells

by Wang T., Hou C., Ren Z., Pan Y., Jia J., Zhang H., Bai F., Zhang P., Zhu H., He Y., Luo S., Li L., Luan S. (2015)

in Nature Communications 6, Article number:6057 –

doi:10.1038/ncomms7057 – 

http://www.nature.com/ncomms/2015/150120/ncomms7057/full/ncomms7057.html

Abstract

Increasing ​carbon dioxide (​CO2) levels in the atmosphere have caused global metabolic changes in diverse plant species. ​CO2 is not only a carbon donor for photosynthesis but also an environmental signal that regulates stomatal movements and thereby controls plant–water relationships and carbon metabolism. However, the mechanism underlying ​CO2 sensing in stomatal guard cells remains unclear.

Here we report characterization of Arabidopsis ​RESISTANT TO HIGH CO2 (​RHC1), a MATE-type transporter that links elevated ​CO2 concentration to repression of ​HT1, a protein kinase that negatively regulates ​CO2-induced stomatal closing.

We also show that ​HT1 phosphorylates and inactivates ​OST1, a kinase which is essential for the activation of the ​SLAC1 anion channel and stomatal closing. Combining genetic, biochemical and electrophysiological evidence, we reconstituted the molecular relay from ​CO2 to ​SLAC1activation, thus establishing a core pathway for ​CO2 signalling in plant guard cells.

Stomata and light

 

Stomatal characteristics of ferns and angiosperms and their responses to changing light intensity at different habitats

by Xiong H., Ma C.-E., Li L., Zeng H., Guo D.-L. (2014)

in Chinese Journal Plant Ecology  2014, Vol. 38 Issue (8): 868-877    DOI: 10.3724/SP.J.1258.2014.00081

Abstract

Aims Stomata are critical in controlling the exchange of water vapour and carbon dioxide and maintaining the balance between plant water and carbon relations. Here, we investigated the effects of habitat (open and understory) and plant type (ferns and angiosperms) on stomatal morphology and stomatal responses to changing light intensity.

Methods We measured stomatal morphology and stomatal conductance in response to transitions in light intensity in five ferns and four angiosperms from different habitats. To increase the sample size, we also collected data on stomatal characteristics for 45 ferns and 70 angiosperms from published studies.

Important findings For all the nine species, the plants in open-habitat had significantly greater stomatal density, shorter stomatal length and greater sensitivity to decreasing light intensity than those in the understory, but the effect of plant type was not significant. Combined analysis with published data indicated that the effects of both habitat and plant type on stomatal morphology were significant. As stomatal sensitivity was closely linked to stomatal morphology, more and smaller stomata might enable angiosperms to respond more quickly to environmental perturbations than ferns. We conclude that both habitat and plant type affect the stomatal response to light.

See the text: CJPE

Stomata and light intensity

 

Stomatal characteristics of ferns and angiosperms and their responses to changing light intensity at different habitats

by Xiong H., Ma C.-E., Li L., Zeng H., Guo D.-L. (2014)

in CJPE  2014, Vol. 38 Issue (8): 868-877

Abstract

Aims

Stomata are critical in controlling the exchange of water vapour and carbon dioxide and maintaining the balance between plant water and carbon relations. Here, we investigated the effects of habitat (open and understory) and plant type (ferns and angiosperms) on stomatal morphology and stomatal responses to changing light intensity.
Methods

We measured stomatal morphology and stomatal conductance in response to transitions in light intensity in five ferns and four angiosperms from different habitats. To increase the sample size, we also collected data on stomatal characteristics for 45 ferns and 70 angiosperms from published studies.

Important findings

For all the nine species, the plants in open-habitat had significantly greater stomatal density, shorter stomatal length and greater sensitivity to decreasing light intensity than those in the understory, but the effect of plant type was not significant. Combined analysis with published data indicated that the effects of both habitat and plant type on stomatal morphology were significant. As stomatal sensitivity was closely linked to stomatal morphology, more and smaller stomata might enable angiosperms to respond more quickly to environmental perturbations than ferns. We conclude that both habitat and plant type affect the stomatal response to light.

See the text: CJPE