We developed a method for preparing starfish chromosomes from embryos. Blastulae were treated with colchicine (0.2–4.0 mg/ml), dissociated into single blastomeres by pippeting, swollen with 7% sodium citrate, and fixed with methanol: acetic acid (3:1). The fixed cells were dropped on a slide and air-dried. We examined the chromosome number in five species of asteroids belonging to 4 families (Luidiidae, Astropectinidae, Asterinidae, and Asteriidae), and all had a diploid number of 44. We analyzed the karyotype in 4 of the species, and all were different. We visualized the nucleolus organizer regions of an Asterina species and an Asterias species and found them to be quite different from each other.
How to translate text using browser tools
1 October 2002
Chromosomes of Japanese Starfishes
Kyoko Saotome,
Mieko Komatsu
asteroids
brittle stars
karyotype
nucleolus organizer regions (NORs)
ophiuroids