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Formation of the Primary Plasmodesmata
The formation of primary plasmodesmata occurs during the part of the cellular division process where the ((endoplasmic reticulum ))and the new plate are fused together, this process results in the formation of a cytoplasmic pore (or cytoplasmic sleeve). The desmotubule, also known as the appressed ER, forms alongside the cortical ER. Both the appressed ER and the cortical ER are packed tightly together, thus leaving no room for any luminal space. It is proposed that the appressed ER acts as a ((membrane transportation)) route in the plasmodesmata. When filaments of the cortical ER are entangled in the formation of a new cell plate, plasmodesmata formation occurs in land plants. It is hypothesized that the appressed ER forms due to a combination of pressure from a a growing cell wall and interaction from ER and PM proteins. Primary plasmodesmata are often present in areas where the cell walls appear to be thinner. This is due to the fact that as a cell wall expands, the abundance of the primary plasmodesmata decreases. In order to further expand plasmodesmal density during cell wall growth secondary plasmodesmata are produced. The process of secondary plasmodesmata formation is still to be fully understood, however various degrading enzymes and ER proteins are said to stimulate the process.

Through dilation, active gating or structural remodeling the permeability of the plasmodesmata is increased. This increase in plasmodesmata pore permeability allows for larger molecules, or ((macromolecules)), such as signaling molecules, transcription factors and RNA-protein complexes to be transported to various cellular compartments.

Plasmodesmata regulation and structure are regulated by a beta 1,3-glucan polymer known as callous. Callose is found in cell plates during the process of cytokinesis, as this process reaches completion the levels of calls decrease. The only callose rich parts of the cell include the sections of the cell wall that plasmodesmata are present. In order to regulate what is transported in the plasmodesmata, callose must be present. Callose provides the mechanism in which plasmodesmata permeability is regulated. In order to control what is transported between different tissues, the plasmodesmata undergo several specialized conformational changes.

Formation of Plasmodesmata in Cotton Fibers
Using cotton fibers and fluorescence, studies revealed the correlation of maintaining high turgor pressure and elongation. This was depicted during transient inhibition of plasmodesmata connectivity. During elongation florescent reporter transportation was blocked from the phloem into the fiber. Using ultrastructural imaging it was discovered that the plasmodesmata that connect the fiber to the seed coat become further complex as elongation occurred. With immunogold labeling, callose levels present at the fiber base during elongation. Callose accumulation decreased as fiber-specific Beta 1-3 glucanase (GhGlul) was introduced and the plasmodesmata re-opened. The transportation of fluorescent symplastic dyes during elongation associated with the failure for plasmodesmata to close at any point during elongation.