Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Glucose Transporters

Glucose Transporters

Glucose transporters facilitate the transport of glucose across the cell membrane. In addition to glucose, some glucose transporters can also aid the movement of other hexoses such as fructose, mannose, and galactose.
Facilitated diffusion-glucose transporters (GLUTs) are encoded by the solute-linked carrier (SLC) family 2, subfamily A gene family, or SLC2A. The 14 GLUT protein members are distributed into three classes:

Lysosomal Hydrolases

Lysosomal Hydrolases

Lysosomes are the site for the degradation of macromolecules and biological polymers released during membrane trafficking events such as secretory, endocytic, autophagic, and phagocytic pathways. The membrane-enclosed area of the lysosome, called the lumen, contains hydrolytic enzymes active in an acidic environment. These acid hydrolases are functional at a pH between 4.5 and 5 and are involved in cellular processes such as cell signaling, energy metabolism, restoration of the plasma membrane,...

Inborn Errors of Metabolism

Inborn Errors of Metabolism

Phenylketonuria (PKU) is a protein metabolism disorder characterized by high blood levels of the amino acid phenylalanine. This results from a mutation in the gene responsible for phenylalanine hydroxylase, an enzyme that converts phenylalanine into tyrosine. When this enzyme is deficient, phenylalanine builds up in the blood, leading to symptoms such as vomiting, rashes, seizures, growth deficiency, and severe mental retardation. An early diagnosis and a diet restricting phenylalanine intake...

Lethal Alleles

Lethal Alleles

Agouti: A Lethal Allele
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...

Aquaporins

Aquaporins

Aquaporins or AQPs are a family of integral membrane proteins whose primary function is to transport water, while some called aquaglyceroporins also transport glycerol. In addition, aquaporins have also been suspected to be involved in transporting volatile substances, such as carbon dioxide and ammonia, across membranes. Such AQPs that act as gas channels are often highly expressed in cells involved in the gaseous exchange, such as red blood cells, epithelial cells, and pulmonary capillaries.

Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase

Pharmacogenetics of Phase II Enzymes: N-acetyltransferase, Thiopurine S-methyltransferase, UDP-glucuronosyltransferase

Phase II biotransformation reactions are essential for detoxifying and eliminating xenobiotics, including many pharmaceutical compounds. These reactions typically involve conjugation, the covalent attachment of polar endogenous groups such as glucuronic acid, sulfate, methyl, or acetyl moieties to functional groups introduced during Phase I metabolism. The resulting conjugates are more water-soluble, enabling efficient renal or biliary excretion.The major classes of Phase II enzymes include...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Undetectable Hydroxyurea Levels in the Majority of Sickle Cell Disease Patients, Especially in Young Children.

American journal of hematology·2026

Same author

The Simplified Diet for PKU: Practices of Swedish Metabolic Dietitians.

Nutrients·2026

Same author

Metabolite Damage and Repair in Health and Disease.

Annual review of nutrition·2026

Same author

Cellular homeostasis of N-acetylneuraminic acid and non-canonical sialic acids is mediated by human N-acetylneuraminate lyase.

Glycobiology·2026

Same author

Clinical Outcomes and Management in Late Diagnosed Siblings Affected With Attenuated GSD Ib.

JIMD reports·2026

Same author

Identification of the function of the metabolite repair enzyme Nit1: the story of a collaboration with Arthur Cooper.

Analytical biochemistry·2025

Search research articles

Related Experiment Video

Updated: May 16, 2026

Transient Expression of Proteins by Hydrodynamic Gene Delivery in Mice

Transient Expression of Proteins by Hydrodynamic Gene Delivery in Mice

Published on: May 5, 2014

Mutations in the AGXT2L2 gene cause phosphohydroxylysinuria.

Maria Veiga-da-Cunha¹, Nanda M Verhoeven-Duif, Tom J de Koning

¹Laboratory of Physiological Chemistry, de Duve Institute and Université Catholique de Louvain, Avenue Hippocrate 75, 1200, Brussels, Belgium, maria.veiga@uclouvain.be.

Journal of Inherited Metabolic Disease

|December 18, 2012

Summary

Phosphohydroxylysinuria is caused by mutations in the AGXT2L2 gene, leading to inactive phosphohydroxylysine phospholyase. This genetic condition may be more common than previously believed.

More Related Videos

In Vitro Enzyme Measurement to Test Pharmacological Chaperone Responsiveness in Fabry and Pompe Disease

In Vitro Enzyme Measurement to Test Pharmacological Chaperone Responsiveness in Fabry and Pompe Disease

Published on: December 20, 2017

Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease

Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease

Published on: April 4, 2018

Related Experiment Videos

Last Updated: May 16, 2026

Transient Expression of Proteins by Hydrodynamic Gene Delivery in Mice

Transient Expression of Proteins by Hydrodynamic Gene Delivery in Mice

Published on: May 5, 2014

In Vitro Enzyme Measurement to Test Pharmacological Chaperone Responsiveness in Fabry and Pompe Disease

In Vitro Enzyme Measurement to Test Pharmacological Chaperone Responsiveness in Fabry and Pompe Disease

Published on: December 20, 2017

Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease

Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease

Published on: April 4, 2018

Area of Science:

Biochemistry
Genetics
Molecular Biology

Background:

Phosphohydroxylysinuria is a rare disorder with unidentified genetic cause.
Previous cases presented with neurological symptoms, but the underlying enzyme or gene was unknown.

Purpose of the Study:

To investigate the genetic basis of phosphohydroxylysinuria.
To test the hypothesis that mutations in the AGXT2L2 gene cause this condition.

Main Methods:

DNA analysis of a patient with joint hyperlaxicity.
Gene sequencing and identification of mutations (p.Gly240Arg and p.Glu437Val).
Recombinant protein expression and functional assays in E. coli and HEK293T cells.

Main Results:

Identified two heterozygous mutations in the AGXT2L2 gene in the patient.
Mutated AGXT2L2 proteins were insoluble and inactive, unlike the soluble, active wild-type protein.
Null alleles for the identified mutations are present at low frequencies in populations, suggesting the condition is underdiagnosed.

Conclusions:

Phosphohydroxylysinuria results from mutations in the AGXT2L2 gene, causing phosphohydroxylysine phospholyase deficiency.
The varied clinical presentations suggest it is not exclusively a neurometabolic disease.
The condition might be more prevalent than previously recognized due to underdiagnosis.