Related Experiment Video
Updated: Aug 10, 2026
05:30
Mouse Eye Enucleation for Remote High-throughput Phenotyping
Published on: November 19, 2011
Lysosomal dysfunctions associated with mutations at mouse pigment genes
Genetics
|May 1, 1979
Summary
Mouse pigment mutants reveal critical genes controlling lysosome function and enzyme secretion. Three mutants (pale ear, pearl, pallid) show altered lysosomal enzyme levels and reduced kidney enzyme secretion into urine.
Area of Science:
- Cell Biology
- Genetics
- Biochemistry
Background:
- Melanosomes and lysosomes share structural and biosynthetic pathways.
- Mouse pigment mutants offer a model to study organelle biogenesis and function.
Purpose of the Study:
- Investigate if genes affecting melanosome structure/function also impact lysosomes.
- Characterize the lysosomal defects in specific mouse pigment mutants.
Main Methods:
- Screened 31 mouse pigment mutants for alterations in kidney lysosomal enzyme concentrations.
- Assayed kidney beta-glucuronidase, beta-galactosidase, and alpha-mannosidase activities.
- Measured lysosomal enzyme secretion rates from kidney to urine and protein synthesis rates.
Main Results:
- Six mutants exhibited increased kidney beta-glucuronidase.
- Pale ear, pearl, and pallid mutants showed coordinate increases in multiple lysosomal enzymes.
- These three mutants displayed significantly reduced lysosomal enzyme secretion into urine.
- Pearl and pallid mutants also showed increased lysosomal enzyme synthesis rates.
Conclusions:
- Genes controlling melanosome biogenesis can also affect lysosome function.
- Mutations in pale ear, pearl, and pallid genes disrupt lysosomal enzyme secretion and concentration.
- These findings highlight critical genes involved in the biogenesis and processing of related subcellular organelles.
Related Concept Videos
01:33Pleiotropy
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
01:39Mutations
Overview
01:22Lysosomal 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,...
02:41Lethal 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...
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...