Sodium/potassium-transporting ATPase subunit alpha-3 is an
enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...
that in humans is encoded by the ''ATP1A3''
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
.
Function
The
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
encoded by this gene belongs to the family of
P-type cation transport ATPase
ATPases (, Adenosine 5'-TriPhosphatase, adenylpyrophosphatase, ATP monophosphatase, triphosphatase, ATP hydrolase, adenosine triphosphatase) are a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion or ...
s, and to the subfamily of
Na+/K+-ATPases. Na
+/K
+-ATPase is an integral
membrane protein
Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane ...
responsible for establishing and maintaining the
electrochemical gradient
An electrochemical gradient is a gradient of electrochemical potential, usually for an ion that can move across a membrane. The gradient consists of two parts:
* The chemical gradient, or difference in Concentration, solute concentration across ...
s of
Na and
K ions across the
plasma membrane
The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extr ...
. These gradients are essential for
osmoregulation
Osmoregulation is the active regulation of the osmotic pressure of an organism's body fluids, detected by osmoreceptors, to maintain the homeostasis of the organism's water content; that is, it maintains the fluid balance and the concentration ...
, for sodium-
coupled
''Coupled'' is an American dating game show that aired on Fox from May 17 to August 2, 2016. It was hosted by television personality, Terrence J and created by Mark Burnett, of '' Survivor'', '' The Apprentice'', '' Are You Smarter than a 5th ...
transport
Transport (in British English) or transportation (in American English) is the intentional Motion, movement of humans, animals, and cargo, goods from one location to another. Mode of transport, Modes of transport include aviation, air, land tr ...
of a variety of
organic and
inorganic
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemistry''.
Inor ...
molecules, and for
electrical excitability of
nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons). Nerves have historically been considered the basic units of the peripheral nervous system. A nerve provides a common pathway for the Electrochemistry, electrochemical nerv ...
and
muscle
Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contra ...
. This
enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...
is composed of two subunits, a large
catalytic
Catalysis () is the increase in reaction rate, rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst ...
subunit (alpha) and a smaller
glycoprotein
Glycoproteins are proteins which contain oligosaccharide (sugar) chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known a ...
subunit (beta). The catalytic subunit of Na
+/K
+-ATPase is encoded by multiple genes. This gene encodes an alpha 3 subunit.
ATP1A3 is expressed early in human development, likely underlying pathophysiology related to several ATP1A3 related diseases.
Clinical significance
Disease causing variants of the ''ATP1A3'' gene are known to cause a variety of movement disorders and epilepsies. The known associations include a variety of syndromes, in approximate order of presentation:
# Malformation of Cortex Development, including
polymicrogyria
Polymicrogyria (PMG) is a condition that affects the development of the human brain by multiple small gyri ( microgyri) creating excessive folding of the brain leading to an abnormally thick cortex. This abnormality can affect either one region of ...
;
# Developmental and epileptic encephalopathy 99 (DEE99);
#
Alternating hemiplegia of childhood
Alternating may refer to:
Mathematics
* Alternating algebra, an algebra in which odd-grade elements square to zero
* Alternating form, a function formula in algebra
* Alternating group, the group of even permutations of a finite set
* Alternat ...
2 (AHC2);
#
Cerebellar ataxia
Cerebellar ataxia is a form of ataxia originating in the cerebellum. Non-progressive congenital ataxia (NPCA) is a classical presentation of cerebral ataxias.
Cerebellar ataxia can occur as a result of many diseases and may present with symptoms ...
, Areflexia, Pes cavus, Optic atrophy and Sensorineural hearing loss (
CAPOS/CAOS syndrome);
# Very early-onset
schizophrenia
Schizophrenia () is a mental disorder characterized variously by hallucinations (typically, Auditory hallucination#Schizophrenia, hearing voices), delusions, thought disorder, disorganized thinking and behavior, and Reduced affect display, f ...
;
#
Rapid-onset dystonia parkinsonism (RDP, also known as DYT12);
# Fever-induced paroxysmal weakness and encephalopathy (FIPWE);
# Recurrent episodes of
cerebellar ataxia
Cerebellar ataxia is a form of ataxia originating in the cerebellum. Non-progressive congenital ataxia (NPCA) is a classical presentation of cerebral ataxias.
Cerebellar ataxia can occur as a result of many diseases and may present with symptoms ...
(RECA).
In mice, mutations in this gene are associated with
epilepsy
Epilepsy is a group of Non-communicable disease, non-communicable Neurological disorder, neurological disorders characterized by a tendency for recurrent, unprovoked Seizure, seizures. A seizure is a sudden burst of abnormal electrical activit ...
. By manipulating this gene in the offspring of such mice, epilepsy can be avoided.
References
Further reading
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External links
GeneReview/NCBI/NIH/UW entry on Rapid-Onset Dystonia Parkinsonism*
{{ATPases