Electron-microscopic studies of iodine-binding and peroxidase activity in the endostyle of the larval amphioxus (Branchiostoma lanceolatum)

Fredriksson, G.; Öfverholm, Torsten; Ericson, Lars

doi:10.1007/bf00217169

Cited by 34 publications

(18 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, PERTs are the only transmembrane peroxidases and Bf_67515 is the only amphioxus sequence harboring a putative transmembrane domain (as predicted by TMpred) located at the same position as in vertebrate PERTs (sites 752-776 corresponding to the sites 847 to 871 in the human PERT). Moreover, peroxidase activity has been located in the endostyle of amphioxus larvae in the outer surface of plasma membranes as well as to the inner surface of membranes in cytoplasmic compartments (Fredriksson et al 1985). Additionally, the orthologous sequence from B. belcheri (Fig.…”

Section: Evolution Of Members Of the Th Signaling Pathwaymentioning

confidence: 98%

“…Secondly, both T 3 and T 4 have been detected in amphioxus (Covelli et al 1960). Thirdly, fixation of iodine was reported in the endostyle of amphioxus (Fredriksson et al 1985) and was shown to be dependent on peroxidase activity. Fourthly, a protein with biochemical properties similar to thyroglobulin has been described in amphioxus (Monaco et al 1981).…”

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

The amphioxus genome enlightens the evolution of the thyroid hormone signaling pathway

et al. 2008

View full text Add to dashboard Cite

Thyroid hormones (THs) have pleiotropic effects on vertebrate development, with amphibian metamorphosis as the most spectacular example. However, developmental functions of THs in non-vertebrate chordates are largely hypothetical and even TH endogenous production has been poorly investigated. In order to get better insight into the evolution of the thyroid hormone signaling pathway in chordates, we have taken advantage of the recent release of the amphioxus genome. We found amphioxus homologous sequences to most of the genes encoding proteins involved in thyroid hormone signaling in vertebrates, except the fast-evolving thyroglobulin: sodium iodide symporter, thyroid peroxidase, deiodinases, thyroid hormone receptor, TBG, and CTHBP. As only some genes encoding proteins involved in TH synthesis regulation were retrieved (TRH, TSH receptor, and CRH receptor but not their corresponding receptors and ligands), there may be another mode of upstream regulation of TH synthesis in amphioxus. In accord with the notion that two whole genome duplications took place at the base of the vertebrate tree, one amphioxus gene often corresponded to several vertebrate homologs. However, some amphioxus specific duplications occurred, suggesting that several steps of the TH pathway were independently elaborated in the cephalochordate and vertebrate lineages. The present results therefore indicate that amphioxus is capable of producing THs. As several genes of the TH signaling pathway were also found in the sea urchin genome, we propose that the thyroid hormone signaling pathway is of ancestral origin in chordates, if not in deuterostomes, with specific elaborations in each lineage, including amphioxus.

show abstract

Section: Evolution Of Members Of the Th Signaling Pathwaymentioning

confidence: 98%

Section: Introductionmentioning

confidence: 97%

The amphioxus genome enlightens the evolution of the thyroid hormone signaling pathway

et al. 2008

View full text Add to dashboard Cite

show abstract

“…It is the mucus nonproducing, smallest, most dorsal and posterior part that is thought to be the homologue of the thyroid follicles. This hypothesis was based on several arguments: (i) the endostyle and the thyroid gland are located in a similar position in the body plan, (ii) some endostyle cells have thyroid-producing properties such as iodine uptake (Fredriksson et al, 1985;Manzon and Youson, 2002;Thomas, 1956) and TH metabolism (Barrington and Thorpe, 1968;Covelli et al, 1960;Kluge et al, 2005;Manzon and Youson, 2002), (iii) several thyroid-specific genes are expressed during endostyle formation [Ttf1 in lamprey (Kluge et al, 2005)], and (iv) in lamprey, some cells of the endostyle transform into thyroidal follicles during metamorphosis (Fredriksson, 1988).…”

Section: Conservation Of the Th Signaling Pathway In Chordatesmentioning

confidence: 99%

The history of a developmental stage: Metamorphosis in chordates

Paris

Laudet

2008

Genesis

View full text Add to dashboard Cite

Summary: Metamorphosis displays a striking diversity in chordates, a deuterostome phylum that comprises vertebrates, urochordates (tunicates), and cephalochordates (amphioxus). In anuran amphibians, the tadpole loses its tail, develops limbs, and undergoes profound changes at the behavioral, physiological, biochemical, and ecological levels. In ascidian tunicates, the tail is lost and the head tissues are drastically remodeled into the adult animal, whereas in amphioxus, the highly asymmetric larva transforms into a relatively symmetric adult. This wide diversity has led to the proposal that metamorphosis evolved several times independently in the different chordate lineages during evolution. However, the molecular mechanisms involved in metamorphosis are largely unknown outside amphibians and teleost fishes, in which metamorphosis is regulated by the thyroid hormones (TH) T 3 and T 4 binding to their receptors (thyroid hormone receptors). In this review, we compare metamorphosis in chordates and then propose a unifying definition of the larva-to-adult transition, based on the conservation of the role of THs and some of their derivatives as the main regulators of metamorphosis. According to this definition, all chordates (if not, all deuterostomes) have a homologous metamorphosis stage during their postembryonic development. The intensity and the nature of the morphological remodeling varies extensively among taxa, from drastic remodeling like in some ascidians or amphibians to more subtle events, as in mammals. genesis 46:657-672,

show abstract

“…In addition, the developing endostyles of amphioxus, tunicates, and lampreys express many of the same genes as the gnathostome thyroid, including TTF-1 (Nkx2-1), Pax 2/ 5/8, FoxQ1, and TPO (Ogasawara and Satoh, 1998;Kozmik et al, 1999;;Ogasawara et al, 1999Ogasawara et al, , 2000Venkatesh et al, 1999;Hiruta et al, 2005;Kluge et al, 2005;Mazet et al, 2005). Homology of the thyroid and endostyle is also supported by their incorporation of iodine (Fujita and Honma, 1965;Fujita, 1969;Fredriksson et al, 1984Fredriksson et al, , 1985Suzuki, 1985). Interestingly, the T3 thyroid hormone induces metamorphosis in both amphioxus and amphibians (Callery and Ellinson, 2000;Rohr and Concha, 2000;Paris et al, 2008).…”

Section: The Relevance Of Amphioxus To Understanding Craniofacial Birmentioning

confidence: 92%

The basal chordate amphioxus as a simple model for elucidating developmental mechanisms in vertebrates

Koop

Holland

2008

Birth Defects Research Pt C

View full text Add to dashboard Cite

This review examines the basal chordate, amphioxus, as a simple model for providing insights into the development and evolution of the vertebrates, with which it shares many features, including a pharynx perforated with gill slits, a dorsal nerve cord, segmented muscles, and a notochord. Conversely, amphioxus is simpler than vertebrates in lacking neural crest and paired cephalic sensory organs. Amphioxus embryos are less derived than those of vertebrates, because it lacks large quantities of yolk and/or extra-embryonic tissues. Embryogenesis involves only a simple folding of tissue layers. In addition, the amphioxus genome lacks the large-scale gene duplications of vertebrates. However, in spite of the comparative simplicity of amphioxus, its developmental mechanisms are proving to be highly conserved with those of vertebrates. Thus, studies of amphioxus development can shed light on similar, but more complex, development of vertebrates. Such studies are especially interesting for their insights into the genetic basis of craniofacial birth defects in humans.

show abstract

Electron-microscopic studies of iodine-binding and peroxidase activity in the endostyle of the larval amphioxus (Branchiostoma lanceolatum)

Cited by 34 publications

References 26 publications

The amphioxus genome enlightens the evolution of the thyroid hormone signaling pathway

The amphioxus genome enlightens the evolution of the thyroid hormone signaling pathway

The history of a developmental stage: Metamorphosis in chordates

The basal chordate amphioxus as a simple model for elucidating developmental mechanisms in vertebrates

Contact Info

Product

Resources

About