Step I Lipophilic Molecule Receptors

[seminoma]

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Firecracker says

Signal transmission through transcription factors: receptors for lipophilic molecules

• steroid hormones, thyroid hormone, vitamin D, retinoids

• Lipophilic molecules (steroids, thyroid hormone, vitamin A and D) easily pass through lipid bilayer of cell membrane. Once intracellular, they bind to specific cytoplasmic proteins and pass into nucleus where they change the rate of mRNA transcription.

Is this incorrectly implying that the T3/T4 receptor and Vit A receptor are cytoplasmic? I thought T3/T4 and Vit A were nuclear whereas the steroid receptors (and Vit D) are cytoplasmic?

 

[Mr. Mojo Risin]

Sounds like an overgeneralization to me.

 

[Mr. Mojo Risin]

Also, there was that Estrogen Receptor thread from a few weeks ago that broke it down into cytoplasmic vs nuclear.

 

[Macaroon_Berry]

As far as I know, out of the common lipophilic receptors, all the important ones are cytoplasmic except for thyroid hormone receptors which are nuclear. I haven't heard of the Vit A receptors being nuclear, so perhaps someone else may know?