Assaying how the oxytocin-vasopressin locus is regulated using CRISPR/Cas9 genome editing in mice.

CHASELON D; CAMARANO AC; RUBINSTEIN M; DE SOUZA FS

Buenos Aires

Congreso; Xth Meeting of the Latin American Society of Developmental Biology; 2019

Latin American Society for Developmental Biology

Oxytocin (OXT) and vasopressin (AVP) are both small neuropeptides synthesized bymagnocellular (MCN) and parvocelullar (PVC) neurons in the paraventricular (PVN) and supraoptic (SON) nuclei of the hypothalamus. The role of these neuropeptides include those of control of hydromineral homeostasis, smooth muscle contraction during lactation and parturition and maternal behavior. Both genes have very similar peptide sequences and are located beside each other, forming a small gene cluster. In spite of this, OXT and AVP show a highly selective cell-type specific expression, with less than 3% of colocalization of OXT and AVP being observed in the hypothalamus. Analyses of available information in mammalian genomic databases revealed the presence of three regions of interest. Two binding sites for CTCF are present in the cluster, one between both genes and another upstream of AVP. Since CTCF is a factor linked to insulator activity, these regions could function as insulators. In addition, we found an extremely conserved region upstream of AVP which contains various motifs for the binding of transcription factors found in the PVN and SON, thus displaying attributes of anenhancer. In order to determine the role of these putative regulatory elements we are employing the CRISPR-Cas9 genome editing technique to eliminate the mentioned regions in mice. Once accomplished these genetic modifications we will analyze changes in the expression of OXT-AVP and neighboring loci.