Membrane steroid receptors (mSRs), also called extranuclear steroid receptors, are a class of

cell surface receptor Cell surface receptors (membrane receptors, transmembrane receptors) are receptors that are embedded in the plasma membrane of cells. They act in cell signaling by receiving (binding to) extracellular molecules. They are specialized integral m ...

s activated by

endogenous Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, ...

steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and ...

s that mediate rapid, non-genomic

signaling In signal processing, a signal is a function that conveys information about a phenomenon. Any quantity that can vary over space or time can be used as a signal to share messages between observers. The '' IEEE Transactions on Signal Processing' ...

via modulation of intracellular signaling cascades. mSRs are another means besides classical

nuclear Nuclear may refer to: Physics Relating to the nucleus of the atom: *Nuclear engineering *Nuclear physics *Nuclear power *Nuclear reactor *Nuclear weapon *Nuclear medicine *Radiation therapy *Nuclear warfare Mathematics *Nuclear space *Nuclear ...

steroid hormone receptor Steroid hormone receptors are found in the nucleus, cytosol, and also on the plasma membrane of target cells. They are generally intracellular receptors (typically cytoplasmic or nuclear) and initiate signal transduction for steroid hormones which ...

s (SHRs) for steroids to mediate their

biological effect In evolutionary biology, function is the reason some object or process occurred in a system that evolved through natural selection. That reason is typically that it achieves some result, such as that chlorophyll helps to capture the energy of sunl ...

s. SHRs can produce slow genomic responses or rapid, non-genomic responses in the case of mSRs.

List of membrane steroid receptors

Known groups of mSRs, by ligand, include: * Membrane sex steroid receptors ** Membrane estrogen receptors (mERs) – GPER, ER-X, ERx, G_q-mER; Nav1.2; palmitoylated nuclear receptors **

Membrane progesterone receptor Membrane progesterone receptors (mPRs) are a group of cell surface receptors and membrane steroid receptors belonging to the progestin and adipoQ receptor (PAQR) family which bind the endogenous progestogen and neurosteroid progesterone, as well as ...

s (mPRs) – PAQRs ( mPRα, mPRβ, mPRγ, mPRδ, mPRϵ); PGRMC1, PGRMC2; ** Membrane androgen receptors (mARs) –

GPRC6A G protein-coupled receptor family C group 6 member A (GPRC6A) is a protein that in humans is encoded by the ''GPRC6A'' gene. This protein functions as a receptor of L-α-amino acids, cations (e.g., calcium), osteocalcin, and steroids. It is a me ...

, OXER1, ZIP9;

TRPM8 Transient receptor potential cation channel subfamily M (melastatin) member 8 (TRPM8), also known as the cold and menthol receptor 1 (CMR1), is a protein that in humans is encoded by the ''TRPM8'' gene. The TRPM8 channel is the primary molecular ...

; Cav1.2 * Membrane corticosteroid receptors ** Membrane glucocorticoid receptors (mGRs) –

caveolin In molecular biology, caveolins are a family of integral membrane proteins that are the principal components of caveolae membranes and involved in receptor-independent endocytosis. Caveolins may act as scaffolding proteins within caveolar ...

-associated nuclear receptors; possible unidentified receptors ** Membrane mineralocorticoid receptors (mMRs) – caveolin-associated NRs; diverse putative receptors In addition, PDIA3 is a membrane receptor for the

secosteroid A secosteroid () is a type of steroid with a "broken" ring. The word ''secosteroid ''derives from the Latin verb ''secare'' meaning "to cut", and 'steroid'. Secosteroids are alternatively described as a subclass of steroids; ; or derived from st ...

calcitriol Calcitriol is the active form of vitamin D, normally made in the kidney. It is also known as 1,25-dihydroxycholecalciferol. It is a hormone which binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the ...

, the activated form of

Vitamin D Vitamin D is a group of Lipophilicity, fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group ar ...

References

G protein-coupled receptors Human proteins Steroids Human female endocrine system {{receptor-stub