Fast skeletal muscle myosin heavy chain gene cluster of medakaOryzias latipesenrolled in temperature adaptation

Abstract

Liang C-S, Kobiyama A, Shimizu A, Sasaki T, Asakawa S, Shimizu N, Watabe S. Fast skeletal muscle myosin heavy chain gene cluster of medaka Oryzias latipes enrolled in temperature adaptation. Physiol Genomics 29: [201][202][203][204][205][206][207][208][209][210][211][212][213][214] 2007. First published January 16, 2007; doi:10.1152/physiolgenomics.00078.2006.-To disclose mechanisms involved in temperature acclimation of fish muscle, we subjected eurythermal fish of medaka Oryzias latipes to cloning of myosin heavy chain genes (MYHs). We cloned cDNAs encoding fast skeletal muscle myosin heavy chain (MYH) isoforms from cDNA libraries of medaka acclimated to 10 and 30°C and observed that different MYH cDNA clones are expressed in the two temperatureacclimated fish. Subsequently, we isolated several overlapping MYH contigs by shotgun cloning strategy from a medaka genomic library. Contig assembly of the complete medaka MYH (mMYH) locus of 219 kbp revealed a cluster of tandemly arrayed 11 mMYHs, in which eight genes are actually transcribed, with the remaining three being pseudogenes. Expression analysis of the transcribed genes revealed that two genes were each highly expressed in medaka acclimated to 10 and 30°C, whereas comparatively lower expression levels of the three genes were exclusively observed in medaka acclimated to 30°C. cDNAs of the remaining genes were too underrepresented in the libraries to determine the expression levels, and the transcripts could only be obtained by reverse transcription-polymerase chain reaction. Deduced amino acid sequences in the loop 1 and loop 2 regions of mMYHs were highly variable, suggesting that these isoforms were functionally different. The present findings consolidate our knowledge on teleost MYH multigene family and would provide further insight into the mechanisms by which expressions of individual MYH molecules are fine-tuned with environmental temperature fluctuations with further functional analysis of the genes concerned. cDNA library; genomic bacterial artificial chromosome library; temperature acclimation; myofibrillar Mg 2ϩ -ATPase activity MYOSINS ARE ACTIN-BASED MOLECULAR motors that convert chemical energy released from the hydrolysis of ATP into mechanical force in eukaryotic cells. Numerous myosins comprising 18 classes (48, 52) have been described, including a subgroup of class II that contains sarcomeric myosins functionally to drive muscle contraction. Class II or conventional two-headed myosin is a heterohexamer consisting of two heavy chains (MYHs) of ϳ200 kDa and four light chains of ϳ20 kDa. The NH 2 -terminal half of each MYH folds into a globular head, termed subfragment-1 (S1), which contains an ATP-and an actin-binding site (30). The COOH-terminal halves of two heavy chains form an ␣-helical coiled coil structure, a rod. Rods can be separated further into two fragments by limited proteolysis; an NH 2 -terminal half called subfragment-2 (S2) and a COOH-terminal half of light meromyosin (LMM) (11). Furthermore, tryptic digestion of S1 results in...

Embryonic temperature affects muscle fibre recruitment in adult zebrafish: genome-wide changes in gene and microRNA expression associated with the transition from hyperplastic to hypertrophic growth phenotypes

“…stickleback (Gasterosteus aculeatus), human, Fig. 6; medaka (Oryzias latipes) (Liang et al, 2007)]. A maximum likelihood phylogenetic analysis was performed for complete amino acid sequences of these genes for zebrafish, stickleback and human, within a framework containing in total 13 human MyHC genes (Fig.…”

Fibre type-specific expression patterns of myosin heavy chain genes in adult torafugu Takifugu rubripes muscles

“…Phylogenetic analysis was carried out to compare torafugu MYH genes with those from other fish such as common carp Imai et al, 1997;Nihei et al, 2006), zebrafish (Yelon et al, 1999;Bryson-Richardson et al, 2005) and medaka Liang et al, 2007), whose expression is well known. MYH M86-1 , MYH M2528-1 and MYH M1034 belong to fast type as they were placed in the clade representing fast MYH genes (Nihei et al, 2006;Ikeda et al, 2007), whereas MYH M8248 belongs to slow type and MYH M2126-2 to cardiac type as they were monophyletic with slow-and cardiac-type MYH genes from other fish species, respectively (Fig.2).…”

“…MYH M86-1 , MYH M2528-1 and MYH M1034 belong to fast type as they were placed in the clade representing fast MYH genes (Nihei et al, 2006;Ikeda et al, 2007), whereas MYH M8248 belongs to slow type and MYH M2126-2 to cardiac type as they were monophyletic with slow-and cardiac-type MYH genes from other fish species, respectively (Fig.2). The phylogenetic tree shows that fast-type MYH genes, MYH M2528-1 and MYH M1034 , were placed in the same clade as fast-type MYHemb1 which is expressed in medaka from embryonic to adult stages , whereas MYH M86-1 was placed in the same clade as fast-type mMYH-11 which is expressed in adult medaka acclimated to 30°C (Liang et al, 2007). MYH M5 was a unique MYH as its phylogenetic position was independent of any other MYH genes, whereas MYH M880 was monophyletic with zebrafish atrial MYH (Fig.2).…”

Expression of multiple slow myosin heavy chain genes reveals a diversity of zebrafish slow twitch muscle fibres with differing requirements for Hedgehog and Prdm1 activity

“…In teleost fish, such as carp and medaka, different MyHC genes are expressed during different developmental stages and at different water temperatures (Liang et al, 2007;Nihei et al, 2006;Ono et al, 2006). The previously described zebrafish smyhc1 gene (BrysonRichardson et al, 2005;Nakano et al, 2004;Rauch et al, 2003) is within a tandem array of five MyHC genes that has been extensively studied on a genomic sequence basis as a classic example of gene conversion events (McGuigan et al, 2004).…”