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Scientists have discovered a new gene that regulates the development of stomata. This gene is called HIC and is found in the Arabidopsis thaliana plant. Researches have found that plants with a dominant allele of the gene do not develop stomata at all, while the wild type recessive allele has a big increase in stomatal development. The researchers believe that the gene is involved in plants’ response to rising CO2 levels in the atmosphere.

Coronatine-biosynthesis-defective (cor) mutant

A plant’s stomata respond to both live bacteria and PAMPs by closing and opening. A plant’s guard cells use coronatine as a defense against these agents. Hence, if a plant is missing stomata, it would become susceptible to secondary infections, such as aphids.

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A plant’s response to rising CO2 levels is largely determined by its response to its environment. Hence, a plant’s response to changing CO2 levels may be partly governed by its genetics. However, it is not known whether a plant would be able to respond to changing CO2 levels without stomata.

A plant’s stomata may be responsible for regulating plant hormones. An example of this is the F-box protein, which binds to JA-Ile, which is a plant hormone. This protein is degraded by the 26S proteasome in a SCFCOI1-dependent manner. COI1 also interacts with the JAZ protein, which is a repressor of the JA signaling pathway. Both proteins have been shown to interact in yeast cells when JA-Ile (108) or COR are present.

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The stomata are composed of specialized epidermal cells called guard cells that regulate the rate of water loss and water exchange. They can change size in response to a variety of environmental stimuli. Changes in light intensity, CO2 concentration, and relative humidity all affect stomatal movement. In addition, the presence of abscisic acid plays a vital role in the signaling of guard cells. It is also responsible for the regulation of stomatal closure under drought stress.

The stomata also play a role in plant-fungal interactions. A transgenic plant called Nicotiana tabacum recognizes a fungal defense elicitor, which activates a series of outward-rectifying K+ channels and inhibits inward-rectifying K+ channels. However, the biological significance of this response is not fully understood.