title: Differential gene expression patterns and colocalization of ATP-gated P2X6/P2X4 ion channels during rat small intestine ontogeny.
abstract: Gene coding for ATP-gated receptor ion channels (P2X1-7) has been associated with the developmental process in various tissues; among these ion channel subtypes, P2X6 acts as a physiological regulator of P2X4 receptor functions when the two receptors form heteroreceptors. The P2X4 receptor is involved in pain sensation, the inflammatory process, and body homeostasis by means of Mg(2+) absorption through the intestine. The small intestine is responsible for the absorption and digestion of nutrients; throughout its development, several gene expressions are induced that are related to nutrients received, metabolism, and other intestine functions. Previous work has shown a differential P2X4 and P2X6 protein distribution in the small intestine of newborn and adult rats; however, it is not well-known at what age the change in the relationship between the gene and protein expression occurs and whether or not these receptors are colocalized. In this work, we evaluate P2X4 and P2X6 gene expression patterns by qPCR from embryonic (E18, P0, P7, P17, P30) to adult age in rat gut, as well as P2X6/P2X4 colocalization using qRT-PCR and confocal immunofluorescence in proximal and distal small intestine sections. The results showed that P2X6 and P2X4 gene expression levels of both receptors decreased at the embryonic-perinatal transition, whereas from ages P17 to P30 (suckling-weaning transition) both receptors increased their gene expression levels. Furthermore, P2X4 and P2X6 proteins were expressed in a different way during rat small intestine development, showing a higher colocalization coefficient at age P30 in both intestine regions. Those results suggest that purinergic receptors may play a role in intestinal maturation, which is associated with age and intestinal region.
authors.affiliation: Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico. Electronic address: 25.kmpo@gmail.com.
authors.forename: Karla
authors.initials: K
authors.lastname: Padilla
authors.affiliation: Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico. Electronic address: david_gm2@hotmail.com.
authors.forename: David
authors.initials: D
authors.lastname: Gonzalez-Mendoza
authors.affiliation: Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico. Electronic address: lcbsq@yahoo.com.
authors.forename: Laura C
authors.initials: LC
authors.lastname: Berumen
authors.affiliation: Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico. Electronic address: jeec82@yahoo.com.mx.
authors.forename: Jesica E
authors.initials: JE
authors.lastname: Escobar
authors.affiliation: Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Blvd Juriquilla 3001, Juriquilla, Querétaro 76230, Mexico. Electronic address: rmiledi@uci.edu.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Miledi
authors.affiliation: Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario, Querétaro 76010, Mexico. Electronic address: leguga@email.com.
authors.forename: Guadulupe
authors.initials: G
authors.lastname: García-Alcocer
mesh_terms: D000255:Adenosine Triphosphate / Q000235:genetics / Q000378:metabolism; D000818:Animals; D004063:Digestion / Q000235:genetics; D047108:Embryonic Development / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D007421:Intestine, Small / Q000254:growth & development* / Q000378:metabolism; D051381:Rats; D018048:Receptors, Purinergic P2 / Q000096:biosynthesis / Q000235:genetics*; D058848:Receptors, Purinergic P2X4 / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D018048:Receptors, Purinergic P2; D058848:Receptors, Purinergic P2X4; C110590:purinoceptor P2X6; D000255:Adenosine Triphosphate
keywords: ATP-gated ion channels; Ion channel colocalization; Ontogenetic gene expression; Small intestine development