Amphioxus

Lacalli T. and Hou S. (1999). A re-examination of the epithelial sensory cells of Amphioxus (Branchiostoma). Acta Zool 80, 125-134. 

Amphioxus ( 500xl06 years) As for (1) with an eye spot. Some coordination of sight with the body. No evidence of olfactory or hearing senses. Little or no telencephalox or cerebral cortex. Has forebrain, pineal and hypothalamus like systems... 

Clark, J.R., J.M. Patrick, Jr., J.C. Moore, and E.M. Lores. 1987. Waterborne and sediment-source toxicities of six organic chemicals to grass shrimp (Palaemonetes pugio) and amphioxus (Branchiostoma carib-aeum). Arch. Environ. Contam. Toxicol. 16 401-407. 

M. Koyanagi, A. Terakita, K. Kubokawa and Y. Shichida, Amphioxus homologs of Go-coupled rhodopsin and peropsin having 11 -cis- and all-/ram-rctinals as their chromophores. FEBS Lett. 531 (2002) 525-528. 

To the chordates, to Amphioxus This book is also dedicated to those ... 

No one has ever decoded this message, although I can tell you that amphioxus and its kin are aquatic creatures that scientists feel are the evolutionary gateway to humanity, to more developed brains, and to consciousness. Amphioxus, the gate, bom millions of year ago...Why do humans exist The answer quite simply is that amphioxus and its close relatives were born eons ego and lived to survive. 

Pycnogonids, Jerzy Kosinski, Ellery Queen, John F. Kennedy, Agatha Christie, John Cheever, Alfred Knopf, and amphioxus. 

Lancelet is the common name for about 25 species of simple marine animals, which are classified between invertebrates (animals without backbones) and vertebrates (animals, like humans, with backbones). They have a stiff dorsal rod and a notochord, but no vertebrae or heart. Around their mouths, cirri and tentacles move like a bag of nervous worms. They share the same ancestry as amphioxus, as evidenced by their embryonic tongue-barred gill slits. 

There are three subphyla within the Chordata. The first two are tunicates and amphioxus, both primitive, headless animals that will not be discussed here. The third group is the most highly developed and complex, the vertebrates or craniates (they have heads). The vertebrates have a segmented body, a cranium enclosing the brain, a heart, and a notochord or vertebral column. Other characteristics are not consistent, but most vertebrate species have bones of some kind, skin, at least two pairs of trunk appendages, and separate sexes. 

Dysbindin-IA is the full-length isoform, the mouse ortholog of which was the first dysbindin protein identified (Benson et al., 2001). This is the protein meant when dysbindin is used without qualification. Dysbindin-1A is a 351 aa protein in humans orthologs in other species are 339-362 aa in length. Such orthologs have been identified not only in humans and mice, but also in the cow, pig, rat, chicken, frog, zebrafish, and amphioxus ( Table 2.2-1). There is also some evidence for dysbindin-lA in sheep (NP 01119821) and the chimpanzee (XP 001169961) in the NCBI database. All known dysbindin-lA orthologs have one or more PEST domain at or near the end of the CTR (e.g., see Table 2.2-3). 

Satoh G (2005) Characterization of novel GPCR gene coding locus in amphioxus genome gene structure, expression, and phylogenetic analysis with implications for its involvement in chem-oreception. Genesis 41 47-57... 

Sharman, A.C., Shineld, S.M., Holland, P.W.H. 1999. An amphioxus Msx gene expressed predominantly in the dorsal neural tube. Dev. Genes Evol. 209, 260-263. 

Holland, N.D., Panganiban, G., Henyey, E.L., Holland, L.Z. 1996. Sequence and developmental expression of AmphiDll, an amphioxus Distal-less gene transcribed in the ectoderm, epidermis and nervous system insights into evolution of craniate forebrain and neural crest. Development 122, 2911-2920. 

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