TY - JOUR
T1 - Neuropeptide amidation
T2 - Cloning of a bifunctional α-amidating enzyme from Aplysia
AU - Fan, Xuemo
AU - Spijker, Sabine
AU - Akalal, David Benjamin G.
AU - Nagle, Gregg T.
N1 - Funding Information:
We thank Drs K.R. Weiss and D.H. Solomon for cDNA libraries, and Dr R.E. Mains for helpful advice during initial stages of the project. We acknowledge the assistance of the UTMB Protein Chemistry Laboratory, which is supported by the UTMB Educational Cancer Center, for DNA sequence analysis. This investigation was supported by NSF IBN-9511773 (to G.T.N.) and a postdoctoral training fellowship from the NIH (to X.F.). The GenBank accession number for the assembled Aplysia PAM cDNA sequence is AF140271.
PY - 2000/10/20
Y1 - 2000/10/20
N2 - One of the most common mechanisms of posttranslational modifications to generate biologically active (neuro)peptides is the process of peptide α-amidation. The only enzyme known to catalyze this important modification is peptidylglycine α-amidating monooxygenase (PAM): a (bifunctional) zymogen, giving rise to a monooxygenase (PHM) and a lyase (PAL). The highly peptidergic central nervous system and endocrine system of the marine mollusk Aplysia has homologs of various mammalian peptide processing enzymes, including furin, Afurin2, prohormone convertase 1 (PC1), PC2, carboxypeptidase E (CPE) and CPD. Previously, it has been shown that the abdominal ganglion of Aplysia, which contains ~800 peptidergic bag cell neurons, contains the highest specific α-amidating activity. We have identified and cloned multiple overlapping central nervous system and bag cell cDNAs that encode a predicted 748-residue protein that is a member of the PAM family. The protein sequence contains the contiguous sequence of the catalytic domains of PHM and PAL, clearly demonstrating the existence of bifunctional Aplysia PAM, the first invertebrate PAM zymogen with an organization similar to that in vertebrates. None of the characterized clones encoded the so-called exon A domain between the PHM and PAL domains. Furthermore, in a specific search by reverse transcription-polymerase chain reaction of RNA from multiple tissues we could only detect exon A-less transcripts. PAM expression was detected in the central nervous system, and in several endocrine and exocrine organs Aplysia PAM is a candidate prohormone processing enzyme that plays an important role in the processing of Aplysia prohormones in the secretory pathway. (C) 2000 Elsevier Science B.V.
AB - One of the most common mechanisms of posttranslational modifications to generate biologically active (neuro)peptides is the process of peptide α-amidation. The only enzyme known to catalyze this important modification is peptidylglycine α-amidating monooxygenase (PAM): a (bifunctional) zymogen, giving rise to a monooxygenase (PHM) and a lyase (PAL). The highly peptidergic central nervous system and endocrine system of the marine mollusk Aplysia has homologs of various mammalian peptide processing enzymes, including furin, Afurin2, prohormone convertase 1 (PC1), PC2, carboxypeptidase E (CPE) and CPD. Previously, it has been shown that the abdominal ganglion of Aplysia, which contains ~800 peptidergic bag cell neurons, contains the highest specific α-amidating activity. We have identified and cloned multiple overlapping central nervous system and bag cell cDNAs that encode a predicted 748-residue protein that is a member of the PAM family. The protein sequence contains the contiguous sequence of the catalytic domains of PHM and PAL, clearly demonstrating the existence of bifunctional Aplysia PAM, the first invertebrate PAM zymogen with an organization similar to that in vertebrates. None of the characterized clones encoded the so-called exon A domain between the PHM and PAL domains. Furthermore, in a specific search by reverse transcription-polymerase chain reaction of RNA from multiple tissues we could only detect exon A-less transcripts. PAM expression was detected in the central nervous system, and in several endocrine and exocrine organs Aplysia PAM is a candidate prohormone processing enzyme that plays an important role in the processing of Aplysia prohormones in the secretory pathway. (C) 2000 Elsevier Science B.V.
KW - Aplysia californica
KW - Lyase
KW - Monooxygenase
KW - α-Amidating enzyme
UR - http://www.scopus.com/inward/record.url?scp=0034693285&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034693285&partnerID=8YFLogxK
U2 - 10.1016/S0169-328X(00)00173-X
DO - 10.1016/S0169-328X(00)00173-X
M3 - Article
C2 - 11042355
AN - SCOPUS:0034693285
SN - 0169-328X
VL - 82
SP - 25
EP - 34
JO - Molecular Brain Research
JF - Molecular Brain Research
IS - 1-2
ER -