Effects of thyroid hormone level alterations on the development of supraneural series in zebrafish, Danio rerio

The effects of alterations in the level of thyroid hormones (THs) on the development of the supraneural series were studied in zebrafish, Danio rerio. Hyper-and hypothyroidism were revealed to influence the rate and timing of development of the supraneurals. The developmental changes induced by THs result in changes in the definitive number and morphology of supraneural bones. High TH-level leads to an arrested development of the supraneural series resulting in the absence or drastic reduction of the number of elements. TH-deficiency leads to a significant retardation of the development of the supraneural series resulting in the appearance of additional elements. These data may be an important piece of the puzzle that may help our understanding how supraneural number and form has changed in evolution.