Cloning of Ly-5 cDNA

Area of Science:

• Immunogenetics
• Molecular Biology
• Hematopoiesis

Background:

• The Ly-5 locus is key for cell surface glycoproteins, defining hematopoietic cell lineage and developmental stages through molecular isoforms.
• Understanding the Ly-5 locus's composition and isoform regulation is vital for comprehending hematopoietic development.

Purpose of the Study:

• To describe a cDNA clone, pLy-5-68, that specifically identifies the Ly-5 gene.
• To investigate the relationship between the pLy-5-68 clone and Ly-5 isoforms in hematopoietic cells.

Main Methods:

• Restriction fragment length polymorphism (RFLP) analysis using Southern blotting to distinguish mouse DNA.
• RNA transfer blotting to assess pLy-5-68 reactivity with different cell types.
• Comparison of mRNA sizes reactive with pLy-5-68 in cells expressing different Ly-5 isoforms.

Main Results:

• The pLy-5-68 clone demonstrated Ly-5 specificity through RFLP, correlating with serological Ly-5 allotypes across mouse strains.
• A unique RFLP pattern (Ly-5c) was observed in ST/bJ mice, distinct from B6 (Ly-5a) and B6-Ly-5b congeneic mice.
• pLy-5-68 reacted positively with Ly-5+ cells and showed size differences in reactive mRNA corresponding to Ly-5 protein isoform variations (200-kDa vs. 220-kDa).

Conclusions:

• The pLy-5-68 cDNA clone is a reliable marker for the Ly-5 gene and its associated allotypes.
• The clone's reactivity patterns support its role in identifying Ly-5 isoforms related to hematopoietic development stages.
• Differential mRNA sizes detected by pLy-5-68 reflect the distinct protein isoforms of Ly-5.