Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Human mast cell tryptase isoforms: separation and examination of substrate-specificity differences

S S Little1, D A Johnson

  • 1Department of Biochemistry, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City 37614-0581, USA.

The Biochemical Journal
|April 15, 1995
PubMed
Summary

Human lung mast cell tryptase (HLT) exists as two distinct isoforms, high-HLT and low-HLT, differing in substrate specificity and cleavage rates. These isoforms may arise from distinct gene products or post-translational modifications.

Related Concept Videos

You might also read

Related Articles

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

Sort by
Same author

Donepezil treatment restores the ability of estradiol to enhance cognitive performance in aged rats: evidence for the cholinergic basis of the critical period hypothesis.

Hormones and behavior·2009
Same author

Virtual enriched environments in paediatric neuropsychological rehabilitation following traumatic brain injury: Feasibility, benefits and challenges.

Developmental neurorehabilitation·2009
Same author

Salivary secretion, mucin concentrations and Candida carriage in HIV-infected patients.

Oral diseases·2009
Same author

High genetic diversity, phenotypic uniformity, and evidence of outcrossing in sclerotinia sclerotiorum in the columbia basin of washington state.

Phytopathology·2008
Same author

Competitive Fitness of Phytophthora infestans Isolates Under Semiarid Field Conditions.

Phytopathology·2008
Same author

Aggressiveness of Isolates of Phytophthora infestans from the Columbia Basin of Washington and Oregon.

Phytopathology·2008

Area of Science:

  • Biochemistry
  • Enzymology
  • Mast Cell Biology

Background:

  • Mast cells contain tryptases, trypsin-like enzymes existing as tetramers.
  • Tryptases are not inhibited by plasma proteinase inhibitors and cleave substrates like high-molecular-mass kininogen (HMMK) and vasoactive intestinal peptide (VIP).

Purpose of the Study:

  • To separate and characterize the different isoforms of human lung mast cell tryptase (HLT).
  • To investigate the functional differences between HLT isoforms regarding substrate specificity and cleavage rates.

Main Methods:

  • Purification of HLT using cellulose phosphate chromatography.
  • Separation of high- and low-molecular-mass HLT isoforms.
  • Analysis of isoforms using SDS-PAGE and HPLC peptide mapping.

Related Experiment Videos

  • Enzymatic assays using HMMK and VIP as substrates.

    • Main Results:

    • Two HLT isoforms (approx. 29 and 33 kDa) were separated, designated high-HLT and low-HLT.
    • Removal of N-linked carbohydrates resulted in single bands on SDS-PAGE, differing slightly in mass.
    • High-HLT and low-HLT exhibited distinct cleavage specificities for HMMK and VIP.
    • Low-HLT cleaved HMMK more rapidly than high-HLT.

    Conclusions:

    • HLT tetramers are composed of homologous subunits, not mixtures of isoforms.
    • The two HLT isoforms demonstrate differential substrate cleavage, suggesting distinct biological roles.
    • These isoforms may originate from different gene products or post-translational modifications.