TY - JOUR
T1 - Expression of myosin heavy chain mRNA in rat laryngeal muscles
AU - Jung, Hak Hyun
AU - Han, Seung Hoon
AU - Choi, Jong Ouck
PY - 1999
Y1 - 1999
N2 - The composition of myosin heavy chain mRNA was analysed quantitatively in 5 intrinsic laryngeal muscles of rats, using a competitive polymerase chain reaction. Intrinsic laryngeal muscles with the fastest contraction times, e.g. ventricular thyroarytenoid muscle, lateral cricoarytenoid muscle, and vocalis muscle, contained 2 fast isoforms, comprising mainly type 2B myosin heavy chains (52.1, 44.6 and 8.2%, respectively) and type 2X myosin heavy chains (21.9, 37.6 and 80.8%, respectively). Conversely, muscles with slower contraction times, such as posterior cricoarytenoid muscle and cricothyroid muscle, contained more than 85% of 2 fast isoforms; mainly type 2X myosin heavy chains (52.4-72.1%, respectively) and type 2A myosin heavy chains (34.6-25.2%, respectively). The results show a strong correlation between the composition of fast myosin heavy chain isoforms and muscle contraction times. Type 2L myosin heavy chain transcripts specific for laryngeal muscles and extra-ocular muscles were expressed in the order of ventricular thyroarytenoid (9.5%) > lateral cricoarytenoid (4.8%) > vocalis (2.5%) > posterior cricoarytenoid muscle (0.9%), but were not expressed in cricothyroid muscle. Neonatal myosin heavy chain was also expressed in all laryngeal muscles, ranging from 0.04 to 3%, but embryonic myosin heavy chain was expressed in ventricular thyroarytenoid, posterior cricoarytenoid and cricothyroid muscle at very low levels. These results suggest that intrinsic laryngeal muscles have different expression patterns for myosin heavy chain isoforms and may have different regulatory roles related to their functional requirement.
AB - The composition of myosin heavy chain mRNA was analysed quantitatively in 5 intrinsic laryngeal muscles of rats, using a competitive polymerase chain reaction. Intrinsic laryngeal muscles with the fastest contraction times, e.g. ventricular thyroarytenoid muscle, lateral cricoarytenoid muscle, and vocalis muscle, contained 2 fast isoforms, comprising mainly type 2B myosin heavy chains (52.1, 44.6 and 8.2%, respectively) and type 2X myosin heavy chains (21.9, 37.6 and 80.8%, respectively). Conversely, muscles with slower contraction times, such as posterior cricoarytenoid muscle and cricothyroid muscle, contained more than 85% of 2 fast isoforms; mainly type 2X myosin heavy chains (52.4-72.1%, respectively) and type 2A myosin heavy chains (34.6-25.2%, respectively). The results show a strong correlation between the composition of fast myosin heavy chain isoforms and muscle contraction times. Type 2L myosin heavy chain transcripts specific for laryngeal muscles and extra-ocular muscles were expressed in the order of ventricular thyroarytenoid (9.5%) > lateral cricoarytenoid (4.8%) > vocalis (2.5%) > posterior cricoarytenoid muscle (0.9%), but were not expressed in cricothyroid muscle. Neonatal myosin heavy chain was also expressed in all laryngeal muscles, ranging from 0.04 to 3%, but embryonic myosin heavy chain was expressed in ventricular thyroarytenoid, posterior cricoarytenoid and cricothyroid muscle at very low levels. These results suggest that intrinsic laryngeal muscles have different expression patterns for myosin heavy chain isoforms and may have different regulatory roles related to their functional requirement.
KW - Gene expression
KW - Polymerase chain reaction
KW - Rat
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U2 - 10.1080/00016489950181459
DO - 10.1080/00016489950181459
M3 - Article
C2 - 10380749
AN - SCOPUS:0032933195
VL - 119
SP - 396
EP - 402
JO - Acta Oto-Laryngologica
JF - Acta Oto-Laryngologica
SN - 0001-6489
IS - 3
ER -