TY - JOUR
T1 - Gene duplication of C-type natriuretic peptide-4 (CNP4) in teleost lineage elicits subfunctionalization of ancestral CNP
AU - Katayama, Yukitoshi
AU - Saito, Ami
AU - Ogoshi, Maho
AU - Tsuneoka, Yousuke
AU - Mukuda, Takao
AU - Azuma, Morio
AU - Kusakabe, Makoto
AU - Takei, Yoshio
AU - Tsukada, Takehiro
N1 - Funding Information:
We thank Dr. Andre P. Seale of the University of Hawaii for critical reading of the manuscript and Dr. Wataru Iwasaki of Atmosphere and Ocean Research Institute, the University of Tokyo, for providing an eel genome database. We also thank Ms. Masako Ino of Nikon Solutions for the technical assistance of confocal laser microscopy.
Funding Information:
This work was supported in part by JSPS KAKENHI Grants (nos. 20K06242 to TT and 20K15604 to YK), the Scientific research funds to YK from Okayama University.
Publisher Copyright:
© 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
PY - 2022/5
Y1 - 2022/5
N2 - The diversified natriuretic peptide (NP) family, consisting of four CNPs (CNP1-4), ANP, BNP, and VNP, has been identified in the eel. Here, we successfully cloned additional cnp genes from the brain of eel (a basal teleost) and zebrafish (a later branching teleost). The genes were identified as paralogues of cnp4 generated by the third round of whole genome duplication (3R) in the teleost lineage, thereby being named eel cnp4b and zebrafish cnp4-like, respectively. To examine the histological patterns of their expressions, we employed a newly developed in situ hybridization (ISH) chain reaction using short hairpin DNAs, in addition to conventional ISH. Eel cnp4b was expressed in the medulla oblongata, while mRNAs of eel cnp4a (former cnp4) were localized in the preoptic area. In the zebrafish brain, cnp4-like mRNA was undetectable, while the known cnp4 was expressed in both the preoptic area and medulla oblongata. Together with the different mRNA distribution of cnp4a and cnp4b in eel peripheral tissues determined by RT-PCR and ISH, it is suggested that subfunctionalization by duplicated cnp4s in ancestral teleosts has been retained only in basal teleosts. Intriguingly, cnp4b-expressing neurons in the glossopharyngeal-vagal motor complex of the medulla oblongata were co-localized with choline acetyltransferase, suggesting an involvement of Cnp4b in swallowing and respiration functions that are modulated by the vagus. Since teleost Cnp4 is an ortholog of mammalian CNP, the identified localization of teleost Cnp4 will contribute to future studies aimed at deciphering the physiological functions of CNP.
AB - The diversified natriuretic peptide (NP) family, consisting of four CNPs (CNP1-4), ANP, BNP, and VNP, has been identified in the eel. Here, we successfully cloned additional cnp genes from the brain of eel (a basal teleost) and zebrafish (a later branching teleost). The genes were identified as paralogues of cnp4 generated by the third round of whole genome duplication (3R) in the teleost lineage, thereby being named eel cnp4b and zebrafish cnp4-like, respectively. To examine the histological patterns of their expressions, we employed a newly developed in situ hybridization (ISH) chain reaction using short hairpin DNAs, in addition to conventional ISH. Eel cnp4b was expressed in the medulla oblongata, while mRNAs of eel cnp4a (former cnp4) were localized in the preoptic area. In the zebrafish brain, cnp4-like mRNA was undetectable, while the known cnp4 was expressed in both the preoptic area and medulla oblongata. Together with the different mRNA distribution of cnp4a and cnp4b in eel peripheral tissues determined by RT-PCR and ISH, it is suggested that subfunctionalization by duplicated cnp4s in ancestral teleosts has been retained only in basal teleosts. Intriguingly, cnp4b-expressing neurons in the glossopharyngeal-vagal motor complex of the medulla oblongata were co-localized with choline acetyltransferase, suggesting an involvement of Cnp4b in swallowing and respiration functions that are modulated by the vagus. Since teleost Cnp4 is an ortholog of mammalian CNP, the identified localization of teleost Cnp4 will contribute to future studies aimed at deciphering the physiological functions of CNP.
KW - In situ hybridization chain reaction
KW - Molecular evolution
KW - Natriuretic peptide (NP)
KW - Subfunctionalization
KW - Teleosts
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U2 - 10.1007/s00441-022-03596-y
DO - 10.1007/s00441-022-03596-y
M3 - Article
C2 - 35171324
AN - SCOPUS:85124829990
VL - 388
SP - 225
EP - 238
JO - Zeitschrift für Zellforschung und mikroskopische Anatomie (Vienna, Austria : 1948)
JF - Zeitschrift für Zellforschung und mikroskopische Anatomie (Vienna, Austria : 1948)
SN - 0302-766X
IS - 2
ER -