Cloning and sequence analysis of complementary DNA encoding a precursor for chicken natriuretic peptide

Area of Science:

• Cardiovascular Biology
• Molecular Endocrinology
• Comparative Genomics

Background:

• Natriuretic peptides (NPs) are crucial regulators of cardiovascular homeostasis.
• Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are well-characterized mammalian NPs.
• The existence and classification of NPs in avian species remain less understood.

Purpose of the Study:

• To identify and characterize a novel natriuretic peptide in the chicken heart.
• To determine the homology and classification of the identified chicken natriuretic peptide (chNP).
• To investigate the genetic basis of chNP.

Main Methods:

• Isolation and sequencing of a complementary DNA (cDNA) clone encoding the chicken natriuretic peptide precursor (pre-chNP) from a cardiac cDNA library.
• Amino acid sequence analysis of pre-chNP and mature alpha-chNP.
• Comparison of chNP sequence and genetic features with known mammalian natriuretic peptides (ANP and BNP).

Main Results:

• Chicken alpha-natriuretic peptide (alpha-chNP) was identified in the chicken heart.
• Pre-chNP is a 140-residue peptide with a 24-residue signal peptide and mature alpha-chNP at the C-terminus.
• While alpha-chNP showed higher homology to BNP than ANP, significant homology was primarily in the C-terminal region; however, a characteristic AT-rich sequence in the 3'-untranslated region, common in mammalian BNPs, was also found.

Conclusions:

• Chicken natriuretic peptide (chNP) is classified as a brain natriuretic peptide (BNP)-type.
• The genetic and sequence characteristics support the classification of chNP within the BNP family.
• This finding contributes to understanding the evolution and diversity of natriuretic peptides in vertebrates.