FXYD1 Membrane Protein Introduction

Introduction of FXYD1

FXYD1 belongs to the FXYD family of which members share a 35-amino acid signature sequence domain, beginning with the amino acid sequence PFXYD. FXYD1 is a single-pass type I membrane protein, with its N-terminus on the extracellular side of the membrane and removal of its signal sequence. FXYD1 is encoded by the FXYD1 gene which is located at 19q13.1. The molecular mass of FXYD1 is about 10 KDa.

Basic Information of FXYD1
Protein Name Phospholemman
Gene Name FXYD1
Aliases FXYD domain-containing ion transport regulator 1, Sodium/potassium-transporting ATPase subunit FXYD1
Organism Homo sapiens (Human)
UniProt ID O00168
Transmembrane Times Single-pass membrane
Length (aa) 92

Function of FXYD1 Membrane Protein

FXYD1 plays a role in several biological functions, such as chloride channel activity, ion channel binding and sodium channel regulator activity. It is wildly expressed in all kinds of tissues in human, especially in skeletal muscle and heart where it is the main substrate for protein kinase A and C. Besides, its expression is relatively high in brain, placenta, lung, liver, pancreas, uterus, bladder, prostate, small intestine, and colon with mucosal lining. FXYD1 can switch among different conformations with different selectivities for cations and anions. Besides, FXYD1 is able to induce hyperpolarization-activated Cl-selective currents. It has been identified as a tissue-specific regulator of Na, K-ATPase (NKA). FXYDI will inhibit NKA activity when it’s unphosphorylated and stimulate activity when phosphorylated. In addition, the interaction between FXYD1 and NKA causes a small decrease in the external K+ affinity of α1–β1 and α2–β1 isozymes and a nearly 2-fold decrease in the internal Na+ affinity. Beyond that, FXYD1 is associated with female sexual development. It also plays a role in the water channel aquaporin 2 (AQP2) trafficking.

FXYD1 Membrane Protein Introduction Fig.1 Structural model of the α/β/FXYD1 Na, K-ATPase complex (Peter, 2009)

Application of FXYD1 Membrane Protein in Literature

  1. Arystarkhova E., et al. Impaired AQP2 trafficking in Fxyd1 knockout mice: A role for FXYD1 in regulated vesicular transport. Plos One. 2017, 12(11): e0188006. PubMed ID: 29155857

    This article reveals that FXYD1 functions in regulating the water channel aquaporin 2 (AQP2) retention in the apical membrane, and that this involves transfers between raft-like membrane domains in endosomes and plasma membranes.

  2. Thomassen M., et al. Intensive training and reduced volume increases muscle FXYD1 expression and phosphorylation at rest and during exercise in athletes. Am J Physiol Regul Integr Comp Physiol. 2016, 310(7): R659. PubMed ID: 26791827

    Authors in this article study the effect of intensive training in combination with a marked reduction in training volume on phospholemman (FXYD1) expression and phosphorylation at rest and during exercise. They find that a period of high-intensity training with reduced training volume increases expression and phosphorylation levels of FXYD1.

  3. Wujak Ł. A., et al. FXYD1 negatively regulates Na (+)/K (+)-ATPase activity in lung alveolar epithelial cells. Respiratory Physiology & Neurobiology. 2016, 220:54. PubMed ID: 26410457

    Authors in this group find increased expression of FXYD1, FXYD3, and FXYD5 in the lungs of acute respiratory distress syndrome (ARDS) patients. They suspect that FXYD1 overexpression in ARDS patient lungs may limit Na (+)/K (+)-ATPase activity, and contribute to edema persistence.

  4. Fuller W., et al. FXYD1 phosphorylation in vitro and in adult rat cardiac myocytes: threonine 69 is a novel substrate for protein kinase C. American Journal of Physiology - Cell Physiology. 2009, 296(6): C1346. PubMed ID: 19339511

    This article reveals a previously undescribed phosphorylation site in FXYD1, threonine 69 (T69). Acute T69 phosphorylation elicits stimulation of the sodium pump additional to that induced by S63 and S68 phosphorylation.

  5. Thomassen M., et al. Effect of 2-wk intensified training and inactivity on muscle Na+-K+ pump expression, phospholemman (FXYD1) phosphorylation, and performance in soccer players. Journal of Applied Physiology. 2010, 108(4):898-905. PubMed ID: 20133439

    This research reports the three-dimensional structure of the FXYD1/Na, K-ATPase complex. It is essential for understanding the function of FXYD1 and the role of FXYD1 phosphorylation. The article also presents the α/β/FXYD1 structural model and the data.

FXYD1 Preparation Options

To obtain the soluble and functional target protein, the versatile Magic™ membrane protein production platform in Creative Biolabs enables many flexible options, from which you can always find a better match for your particular project. Aided by our versatile Magic™ anti-membrane protein antibody discovery platform, we also provide customized anti-FXYD1 antibody development services.

As a forward-looking research institute as well as a leading customer service provider in the field of membrane protein, Creative Biolabs has won good reputation among our worldwide customers for successfully accomplishing numerous challenging projects including generation of many functional membrane proteins. Please feel free to contact us for more information.


  1. Peter T., et al. (2009). Effects of PKA phosphorylation on the conformation of the Na,K-ATPase regulatory protein FXYD1. Biochimica et Biophysica Acta (BBA) – Biomembranes. 1788(11), 2462-2470.

Online Inquiry

Verification code
Click image to refresh the verification code.


USA: 45-1 Ramsey Road, Shirley, NY 11967, USA
Europe: Heidenkampsweg 58, 20097 Hamburg, Germany
Call us at:
USA: 1-631-381-2994
Europe: 44-207-097-1828
Fax: 1-631-207-8356
Our customer service representatives are available 24 hours a day, 7 days a week. Contact Us