Thyroid hormone regulates the obesity gene tub.
Thyroid hormone T3/T4 is a major regulator of energy metabolism in vertebrates, and defects in thyroid status are frequently associated with changes in body weight. It is demonstrated here that thyroid hormone regulates in vivo and in vitro the tub gene, which when mutated in tubby mice causes obesity, insulin resistance and sensory deficits. Hypothyroidism in rats altered tub mRNA and protein in discrete brain areas. These changes could be attributed to thyroid hormone deficiency since T3/T4 treatment restored normal tub expression. T3 also upregulated tub mRNA within 4-6 h in neuronal cells in culture, suggesting that T3 is a positive regulator of tub gene expression. Thus, these results establish a novel pathway of T3 action and provide an important molecular link between thyroid status and the tubby-associated syndrome.
Koritschoner
N P
NP
1Max-Delbrück-Center for Molecular Medicine MDC, Robert-Rössle Strasse 10, D-13122 Berlin, Germany.
Alvarez-Dolado
M
M
Kurz
S M
SM
Heikenwälder
M F
MF
Hacker
C
C
Vogel
F
F
Muñoz
A
A
Zenke
M
M
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D015152:Blotting, Northern; D001835:Body Weight; D001921:Brain / Q000378:metabolism; D002460:Cell Line; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007037:Hypothyroidism / Q000378:metabolism; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D009154:Mutation; D016716:PC12 Cells; D011506:Proteins / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013963:Thyroid Hormones / Q000502:physiology*; D013997:Time Factors; D015854:Up-Regulation
D048868:Adaptor Proteins, Signal Transducing; D011506:Proteins; D012333:RNA, Messenger; D013963:Thyroid Hormones; C098988:Tub protein, mouse