QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Temple, G. K. Articles by Johnston, I. A. Search for Related Content PubMed PubMed Citation Articles by Temple, G. K. Articles by Johnston, I. A.

Embryonic temperature and the relative timing of muscle-specific genes during development in herring (Clupea harengus L.)

Genevieve K. Temple^*, Nicholas J. Cole and Ian A. Johnston

Gatty Marine Laboratory, Division of Environmental and Evolutionary Biology, School of Biology, University of St Andrews, St Andrews, Fife KY16 8LB, Scotland
Present address: Department of Anatomy and Physiology, Wellcome Trust Biocentre, University of Dundee, Dundee DD1 5EH, Scotland

View larger version (31K): [in a new window]   Fig. 1. Comparison of the deduced partial amino acid sequence of herring MyoD with comparable sequences for zebrafish (Weinberg et al., 1996), trout TMyoD2 (Rescan and Gauvry, 1996), trout TMyoD (Rescan et al., 1994) and carp (Kobiyama et al., 1998). Dashes represent amino acid residues identical to those of herring; dots represent gaps. The boxed area indicates the basic helix–loop–helix domain.

View larger version (23K): [in a new window]   Fig. 2. Comparison of the deduced partial amino acid sequence of herring myogenin with comparable sequences for zebrafish (Chen et al., 2000), trout (Rescan et al., 1995) and carp (Kobiyama et al., 1998). Dashes represent amino acid residues identical to those of herring; dots represent gaps. The boxed area indicates the basic helix–loop–helix domain.

View larger version (18K): [in a new window]   Fig. 3. Comparison of the deduced partial amino acid sequence of herring light meromyosin with comparable sequences for zebrafish (Xu et al., 2000), trout (Gauvry and Fauconneau, 1996) and 10°C-acclimated carp (Hirayama and Watabe, 1997). Dashes represent amino acid residues identical to those of herring; dots represent gaps.

View larger version (51K): [in a new window]   Fig. 4. MyoD expression in herring embryos reared at 8°C. (A) Three-somite embryo; head positioned towards the bottom of the figure. The MyoD transcript accumulates in the adaxial cells prior to expanding into the lateral posterior regions of newly formed somites. (B–G) 15-somite herring embryo; (B–E) transverse sections, arranged most posterior first, showing the accumulation of MyoD transcript in (B) the adaxial cells only and (C–E) the adaxial cells and the somites. (F,G) Sagittal sections, head towards the top of the figure, showing the accumulation of MyoD transcript in the somites and (G) in the adaxial cells of the presomitic mesoderm. n, notochord; pm, presomitic mesoderm. Arrows indicate adaxial cells; arrowheads indicate somites. Scale bars, 50 µm.

View larger version (70K): [in a new window]   Fig. 5. Comparison of MyoD, myogenin and MyHC RNA transcript expression in herring embryos with similar numbers of somites and at a variety of rearing temperatures. (A–E) Expression of MyoD, (F–J) expression of myogenin, (K–O) expression of myosin heavy chain. (A,F) Embryos, dorsal view, head positioned towards the bottom of the figure. All other embryos are positioned anterior to the right. (A,F,K) 15-somite embryos. (B,G,L), 18-, 17- and 18-somite embryos, respectively. (C,H,M), 35-, 34- and 34-somite embryos, respectively. (D,I,N), 49-, 46- and 48-somite embryos, respectively. (E,J,O) Embryos with almost complete segmentation. Arrows indicate adaxial cells; the arrowhead indicates unstained somites. Scale bars, 300 µm.

View larger version (80K): [in a new window]   Fig. 6. MyoD (A–D) and myogenin (E,F) expression in embryos reared at different temperatures. (A) 30-somite embryo reared at 5°C, (B) 30-somite embryo reared at 12°C, (C) 42-somite embryo reared at 5°C, (D) 42-somite embryo reared at 8°C, (E) 17-somite embryo reared at 8°C and (F) 17-somite embryo reared at 12°C. Scale bars, 300 µm.

View larger version (85K): [in a new window]   Fig. 7. Myogenin expression in a 46-somite embryo reared at 8°C. (A) Sagittal section showing the accumulation of myogenin transcript in the caudal somites and the decrease in transcript expression in the more rostral somites. (B–E) Transverse sections, arranged most posterior first, showing the decrease in transcript expression in progressively older (more rostral) somites. n, notochord; g, gut. The arrowhead indicates somites. Scale bars, 300 µm.

View larger version (14K): [in a new window]   Fig. 8. The relationship between the most posterior somite expressing myosin heavy chain (MyHC) transcript and the number of somites in herring embryos incubated at different temperatures. Open circles represent embryos reared at 5°C, filled circles represent embryos reared at 8°C and filled triangles represent embryos reared at 12°C. A common least-squares regression line is shown; slope b=0.97±0.03, mean ± S.E.M., N=49; r2=0.96.