title: Embryonic gene expression and pro-protein processing of proSAAS during rodent development.
abstract: In vitro assays have demonstrated that peptides derived from the recently-identified proSAAS precursor inhibit prohormone convertase 1 (PC1) suggesting that this novel peptide may function as an endogenous inhibitor of PC1. To further understand the role of proSAAS in vivo, we have investigated the expression of proSAAS mRNA and processing of proSAAS during pre- and early postnatal rodent development. In situ hybridization showed that, by embryonic day 12.5 (e12.5) in the rat, proSAAS mRNA was present in essentially all differentiating neurons in the mantle layer of the myelencephalon, metencephalon, diencephalon, spinal cord and several sympathetic ganglia. During later stages of prenatal development, widespread proSAAS expression continues in post-mitotic neurons of both the CNS and PNS and begins in endocrine cells of the anterior and intermediate pituitary. Although proSAAS expression overlaps with PC1 in several regions, its overall expression pattern is significantly more extensive, suggesting that proSAAS may be multifunctional during development. Processed forms of proSAAS are present by at least mid-gestation with marked accumulation of two C-terminal forms, comprising the PC1 inhibitory fragment of proSAAS.
authors.affiliation: Department of Neuroscience and Cell Biology, University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Morgan
authors.forename: Nino
authors.initials: N
authors.lastname: Mzhavia
authors.forename: Bonnie
authors.initials: B
authors.lastname: Peng
authors.forename: Hui
authors.initials: H
authors.lastname: Pan
authors.forename: Lakshmi A
authors.initials: LA
authors.lastname: Devi
authors.forename: John E
authors.initials: JE
authors.lastname: Pintar
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000502:physiology*; D002490:Central Nervous System / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D004745:Enkephalins / Q000096:biosynthesis; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D006728:Hormones / Q000096:biosynthesis; D051379:Mice; D008810:Mice, Inbred C57BL; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009420:Nervous System / Q000196:embryology* / Q000254:growth & development / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides; D009490:Neurosecretory Systems / Q000196:embryology / Q000378:metabolism; D017933:Peripheral Nervous System / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D010902:Pituitary Gland / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D045664:Proprotein Convertase 1 / Q000235:genetics / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D011498:Protein Precursors / Q000096:biosynthesis; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D017434:Protein Structure, Tertiary / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004745:Enkephalins; D006728:Hormones; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; C112832:Pcsk1n protein, mouse; D020033:Protein Isoforms; D011498:Protein Precursors; D012333:RNA, Messenger; C033660:preproenkephalin; D045664:Proprotein Convertase 1