Demonstration of plasminogen‐like protein in amphioxus with implications for the origin of vertebrate liver

Liang, Yujun; Zhang, S. C.

doi:10.1111/j.1463-6395.2006.00228.x

Cited by 18 publications

(11 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is of note that BbPlgl has a calculated molecular mass of approx. 46.7 kDa, which is about half the size of that estimated from Western blotting analysis [19]. Although this difference may be due to the fact that the molecular mass calculated from BbPlgl cDNA has ignored the putative glycosylations, it cannot be ruled out that BbPlgl and the molecule reported by Liang and Zhang [19] are two different molecules.…”

Section: Discussionmentioning

confidence: 86%

“…Previous studies have shown the presence of Plg only in the jawed vertebrates [3,32], and a Plgl molecule has been discovered in the amphioxus B. belcheri, a basal chordate [19]. However, molecular mammalian Plgs [23], BbPlgl is also able to auto-activate at neutral and alkaline pH at 4 • C without the addition of human uPA, and the activation is remarkably accelerated by addition of human uPA.…”

Section: Discussionmentioning

confidence: 99%

“…The primary structure of this protein from different species has been quite consistent, consisting of a pre-activation peptide known as the PAN domain (about 77 amino acid residues), five tandem kringle domains (about 80 residues each), an activation cleavage site (between Arg 561 and Val 562 ; numbering as human Plg) and a catalytic domain including the serine protease triad of His 603 , Asp 646 and Ser 741 [12,17,18]. However, the Plg gene has not been reported thus far in the non-vertebrate chordates or other invertebrate animals, although a plasminogen-like molecule has recently been observed in the primitive chordate amphioxus Branchiostoma belcheri [19]. Moreover, the origin of Plg remains obscure during the course of animal evolution.…”

Section: Abbreviations Usedmentioning

confidence: 99%

See 2 more Smart Citations

A kringle-containing protease with plasminogen-like activity in the basal chordate Branchiostoma belcheri

Liu

Zhang

2009

Bioscience Reports

View full text Add to dashboard Cite

Plg (plasminogen), a member of the serine protease superfamily, is a key component constituting the fibrinolytic system, and its evolutionary origin remains unknown during the course of animal evolution. In the present study, we isolated a cDNA, designated BbPlgl, encoding a kringle-containing protease with plasminogen-like activity from the basal chordate Branchiostoma belcheri. The deduced protein, BbPlgl, consisted of 430 amino acids, which is structurally characterized by the presence of an N-terminal signal peptide of 16 amino acids, 2 kringle domains with a Lys-binding site structure, a serine protease domain with the putative tPA (tissue plasminogen activator)-cleavage site (between Arg297 and Val298), the catalytic triad His237-Asp288-Ser379 expected for protease function, and a potential N-linked glycosylation site, all characteristic of Plgs. Besides, the recombinant refolded BbPlgl was readily activated by human uPA (urokinase plasminogen activator), and exhibited Plg-like activity. BbPlgl was also able to auto-activate at neutral and alkaline pH at 4 degrees C without the addition of uPA, and the activation was accelerated by addition of human uPA. These results demonstrate that BbPlgl is a novel member of the Plg family, with a domain structure of K-K-SP (kringle-kringle-serine protease) lacking the PAN domain, pushing the evolutionary origin of Plg to the protochordate. In addition, BbPlgl displays a tissue-specific expression pattern in B. belcheri, with the most abundant expression in the hepatic caecum and hind-gut, agreeing with the notion that the hepatic caecum of amphioxus is the precursor of the vertebrate liver.

show abstract

Section: Discussionmentioning

confidence: 86%

Section: Discussionmentioning

confidence: 99%

Section: Abbreviations Usedmentioning

confidence: 99%

See 1 more Smart Citation

A kringle-containing protease with plasminogen-like activity in the basal chordate Branchiostoma belcheri

Liu

Zhang

2009

Bioscience Reports

View full text Add to dashboard Cite

show abstract

“…To detail the distribution of BMP2/4 at the wound site, immunohistochemical staining was also conducted on tissue sections of tail regenerates at the wound-healing stage. Processing and immunostaining of the sections was conducted as described previously (Liang and Zhang, 2006). The primary antibody was diluted 1:400 and the secondary antibody (HRP-conjugated goat anti-rabbit IgG; Abcam, ab97051) was diluted 1:600.…”

Section: Immunohistochemistrymentioning

confidence: 99%

BMP signaling is required for amphioxus tail regeneration

et al. 2019

View full text Add to dashboard Cite

Amphioxus, a cephalochordate, is an ideal animal in which to address questions about the evolution of regenerative ability and the mechanisms behind the invertebrate to vertebrate transition in chordates. However, the cellular and molecular basis of tail regeneration in amphioxus remains largely ill-defined. We confirmed that the tail regeneration of amphioxus Branchiostoma japonicum is a vertebrate-like epimorphosis process. We performed transcriptome analysis of tail regenerates, which provided many clues for exploring the mechanism of tail regeneration. Importantly, we showed that BMP2/4 and its related signaling pathway components are essential for the process of tail regeneration, revealing an evolutionarily conserved genetic regulatory system involved in regeneration in many metazoans. We serendipitously discovered that bmp2/4 expression is immediately inducible by general wounds and that expression of bmp2/4 can be regarded as a biomarker of wounds in amphioxus. Collectively, our results provide a framework for understanding the evolution and diversity of cellular and molecular events of tail regeneration in vertebrates.

show abstract

“…If this is correct, it might then be analogous to the so‐called mid‐gut diverticulum of amphioxus (e.g. Barrington, 1937; see also Liang & Zhang, 2006), although this of course is located on the opposite side of the body. Finally, we should note that the amphioxus has no obvious equivalent to the structure(s) identified as the anterior dorsal unit.…”

Section: Phylogenetic Relationships Of Pikaiamentioning

confidence: 99%

Pikaia gracilensWalcott, a stem‐group chordate from the Middle Cambrian of British Columbia

Morris

Caron

2012

Biological Reviews

View full text Add to dashboard Cite

The Middle Cambrian Pikaia gracilens (Walcott) has an iconic position as a Cambrian chordate, but until now no detailed description has been available. Here on the basis of the 114 available specimens we review its anatomy, confirm its place in the chordates and explore with varying degrees of confidence its relationships to both extant and extinct chordates and other deuterostomes. The body of Pikaia is fusiform, laterally compressed and possesses about 100 myomeres. The head is small, bilobed and bears two narrow tentacles. There is no evidence for eyes. Apart from a thin dorsal fin (without finrays) and a series of at least nine bilaterally arranged appendages with possible pharyngeal pores at the anterior end, there are no other external features. In addition to the musculature the internal anatomy includes an alimentary canal, the anterior of which forms a prominent lenticular unit that is almost invariably preserved in positive relief. The cavity is interpreted as pharyngeal, implying that the mouth itself was almost terminal. The posterior extension of the gut is unclear although the anus appears to have been terminal. The most prominent internal structure is a reflectively preserved unit, possibly hollow, termed here the dorsal organ. Although formerly interpreted as a notochord its position and size make this less likely. Its original function remains uncertain, but it could have formed a storage organ. Ventral to the dorsal organ a narrower strand of tissue is interpreted as representing the nerve chord and notochord. In addition to these structures, there is also evidence for a vascular system, including a ventral blood vessel. The position of Pikaia in the chordates is largely based on the presence of sigmoidal myomeres, and the more tentative identification of a notochord. In many other respects, Pikaia differs from the expected nature of primitive chordates, especially as revealed in amphioxus and the Cambrian record (including Cathaymyrus, Haikouichthys, Metaspriggina, Myllokunmingia, and Zhongxiniscus). Whilst the possibility that Pikaia is simply convergent on the chordates cannot be dismissed, we prefer to build a scenario that regards Pikaia as the most stem-ward of the chordates with links to the phylogenetically controversial yunnanozoans. This hypothesis has implications for the evolution of the myomeres, notochord and gills. Finally, the wealth of material of Pikaia indicates that, although by definition there must be some sort of taphonomic imprint, the consistency of preservational details allows a reliable reconstruction of the anatomy and does not significantly erode phylogenetically relevant characters.

show abstract

Demonstration of plasminogen‐like protein in amphioxus with implications for the origin of vertebrate liver

Cited by 18 publications

References 42 publications

A kringle-containing protease with plasminogen-like activity in the basal chordate Branchiostoma belcheri

A kringle-containing protease with plasminogen-like activity in the basal chordate Branchiostoma belcheri

BMP signaling is required for amphioxus tail regeneration

Pikaia gracilensWalcott, a stem‐group chordate from the Middle Cambrian of British Columbia

Contact Info

Product

Resources

About