Expression of preproendothelin-2 splice variant in cat

Area of Science:

• Molecular Biology
• Genetics
• Comparative Physiology

Background:

• Alternative splicing of preproendothelin-2 (PPET2) mRNA has been observed in human tissues, leading to variants lacking critical processing sites.
• Endothelin-2 plays crucial roles in various physiological processes, and its proper processing is vital.

Purpose of the Study:

• To investigate the presence and characteristics of PPET2 splice variants in feline (cat) stomach tissue.
• To identify novel PPET2 mRNA sequences in cats and analyze their potential functional implications.

Main Methods:

• Cloning of the full-length complementary DNA (cDNA) of cat PPET2.
• Organ distribution analysis of PPET2 mRNA using reverse transcriptase-polymerase chain reaction (RT-PCR).
• Subsequent cloning and sequence analysis of amplified PCR products from stomach tissue.

Main Results:

• RT-PCR analysis of cat stomach tissue revealed two PPET2 mRNA fragments: one matching the full-length cDNA and a smaller, unexpected fragment.
• Sequence analysis confirmed the smaller fragment represents a novel splice variant.
• This variant is characterized by the complete deletion of a region corresponding to exon 4 of the PPET2 gene.

Conclusions:

• A novel splice variant of cat PPET2 mRNA, lacking exon 4, is expressed in the stomach.
• This exon deletion may result in a PPET2 variant that lacks a post-translational proteolytic site, similar to human variants.
• Further research is needed to determine the functional consequences of this splice variant in cats.