Table 1.

Effect of postdevelopmental myostatin knockout on expression of contractile protein genes that are downregulated more than fourfold in mice with constitutive myostatin deficiency

Gene	Symbol	Affymetrix probe ID	Constitutive KO/Normal	P	Postdevelopmental KO/Normal	P
Myosin heavy polypeptide 7 (type 1 myosin heavy chain)	Myh7	1448554_s_at	0.09	<10−6	0.74	0.47
				1448553_at	0.14	<10−6	0.79	0.37
				RealtimePCR			0.68	0.27
Myosin light polypeptide 2	Myl2	1448394_at	0.18	<10−6	0.86	0.19
Myosin light polypeptide 3	Myl3	1427768_s_at	0.21	<10−6	0.98	0.84
		1428266_at	0.25	<10−6	1.00	0.99
		1427769_x_at	0.30	<10−6	1.01	0.94
Troponin C, cardiac/slow skeletal	Tnnc1	1418370_at	0.15	<10−6	0.86	0.48
Troponin I, skeletal, slow 1	Tnni1	1450813_a_at	0.20	<10−6	0.74	0.47
Troponin T1, skeletal, slow	Tnnt1	1419606_a_at	0.14	<10−6	0.82	0.48
Tropomyosin 3, gamma	Tpm3	1449997_at	0.12	<10−6	0.83	0.57
		1449996_a_at	0.13	<10−6	0.82	0.63

Data for mice with constitutive knockout (KO) are from Steelman et al. (24), in which the same microarray platform used in the present study was used to examine RNA from pectoral muscles of 5 wk old mice. P refers to significance of difference between knockout and control groups by t-tests without adjustment for multiple comparisons.