Aim &  Background: whole-mount in situ hybridization (wmISH) is a powerful tool to visualize the gene transcript in embryonic tissue. This study aimed at setting up wmISH using digoxygenine-labled RALDH2 antisense riboprobe.

Methods & Materials: The early developing chick embryos were fixed and dehydrated upon dissecting. Following bleaching and protein kinase K treatment, the embryos were hybridized with hybridization buffer and then with the buffer containing RALDH2 antisense riboprobe for 36h. Upon washing with SSC solution and incubation with anti-digoxygenin Ab, the embryos were treated with NBT/BCIP and transferred to NTMT buffer. Some embryos received sense ribobrobe and negative control was considered as a group not treated with any riboprobes.

Results: Following binding the antisense riboprobe to RALDH2 transcript, blue color appeared in somites and neural tube as well as the cardiac tube. No color was detected in the embryonic tissue treated with the sense riboprobe or in untreated group.