GSBS Student Publications
Title
Analysis of the prokineticin 2 system in a diurnal rodent, the unstriped Nile grass rat (Arvicanthis niloticus)
GSBS Program
Neuroscience
UMMS Affiliation
Department of Neurobiology; Weaver Lab; Graduate School of Biomedical Sciences, Neuroscience Program
Date
4-27-2005
Document Type
Article
Medical Subject Headings
Amino Acid Sequence; Animals; Brain Chemistry; Circadian Rhythm; DNA, Complementary; Gene Expression Regulation; In Situ Hybridization; Light; Male; Molecular Sequence Data; Polymorphism, Genetic; Rats; Rodentia; Transcription, Genetic; Vascular Endothelial Growth Factor,; Endocrine-Gland-Derived
Disciplines
Neuroscience and Neurobiology
Abstract
Prokineticin 2 (PK2) is a putative output molecule from the SCN. PK2 RNA levels are rhythmic in the mouse SCN, with high levels during the day, and PK2 administration suppresses nocturnal locomotor activity in rats. The authors examined the PK2 system in a diurnal rodent, Arvicanthis niloticus, to determine whether PK2 or PK2 receptors differ between diurnal and nocturnal species. The major transcript variant of A. niloticus PK2 (AnPK2) encodes a 26-residue signal peptide followed by the presumed mature peptide of 81 residues. Within the grass rat signal sequence, polymorphic sequences and amino acid substitutions were observed relative to mouse and laboratory rats, but the hydrophobic core and cleavage site of the signal sequence were preserved. The mature PK2 peptide is identical among A. niloticus, rat, and mouse. AnPK2 mRNA is rhythmically expressed in the SCN, with peak RNA levels occurring in the morning, preceding peaks of Per1 and Per2 as in mouse SCN. Analysis of prokineticin receptor 2 (PKR2) sequences revealed polymorphisms among the grass rats studied. PKR2 mRNA was expressed in the SCN and paraventricular nuclei of the thalamus and hypothalamus. While further analysis is necessary, there is no clear evidence indicating that a difference in the PK2 ligand/receptor system accounts for diurnality in this rodent species. These data contribute to a growing body of evidence suggesting that the key to diurnality lies downstream of the SCN in A. niloticus.
Rights and Permissions
Citation: J Biol Rhythms. 2005 Jun;20(3):206-18. Link to article on publisher's site
DOI of Published Version
10.1177/0748730405275135
Related Resources
Journal Title
Journal of biological rhythms
PubMed ID
15851527
Repository Citation
Lambert, Christopher M.; Machida, Kazuhiko K.; Smale, Laura; Nunez, Antonio A.; and Weaver, David R., "Analysis of the prokineticin 2 system in a diurnal rodent, the unstriped Nile grass rat (Arvicanthis niloticus)" (2005). GSBS Student Publications. 1731.
https://escholarship.umassmed.edu/gsbs_sp/1731