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Holland, LZ, Gould-Somero M.  1982.  Fertilization Acid of Sea-Urchin Eggs - Evidence That It Is H+, Not Co2. Developmental Biology. 92:549-552.   10.1016/0012-1606(82)90200-7   Website
Gould-Somero, M, Holland LZ.  1975.  Fine-structural Investigation of Insemination Response in Urechis caupo . Developmental Biology . 46(2):358-369.   10.1016/0012-1606(75)90112-8  
Holland, ND, Holland LZ.  1991.  The Fine-Structure of the Growth Stage Oocytes of a Lancelet (= Amphioxus), Branchiostoma-Lanceolatum. Invertebrate Reproduction & Development. 19:107-122.   10.1080/07924259.1991.9672164   AbstractWebsite

Oocytes of the European lancelet (Branchiostoma lanceolatum) were fixed for transmission electron microscopy at Banyuls (French Mediterranean) in mid spring, which is just before the spawning season. Special attention is given to the growth stage (= diplotene) oocytes and to their relations with non-germinal cells of the ovary. At the time of year studied, the ovaries contain both relatively small (7-57-mu-m) and relatively large (97-127-mu-m) oocytes, but none of medium-size. In addition to the usual cell organelles (like free ribosomes, mitochondria, and endoplasmic reticulum), the oocytes include a number of more specialized structures. Nuage is present throughout the growth stage, both adjacent to the nucleus and scattered elsewhere in the cytoplasm. Other specialized structures do not begin to appear until the oocytes attain a certain diameter. The following structures are first detected at the following oocyte diameters: cortical granules, always in close association with Golgi complexes (20-mu-m); vacuoles containing presumed precursors of the vitelline layer (30-mu-m); yolk granules (35-mu-m); and a central vacuole within the nucleolus (50-mu-m). The cytoplasm of the largest oocytes includes a few annulate lamellae and some very unusual striated fibers resembling ciliary rootlets. These fibers, which are banded with a 70-nm periodicity (but are evidently not associated with centrioles), occur only at the animal pole of the oocyte, and their functional significance is unknown. The smaller oocytes have relatively smooth plasma membranes, except where endocytotic pits are abundant, whereas the larger oocytes bear abundant microvilli and are covered by a vitelline layer of dense, granular material. During oocyte growth, areas of contact between the oocytes and neighboring non-germinal cells shrink progressively. In the large oocytes, such contacts are limited to the animal pole, where a few processes from non-germinal cells pass through the vitelline layer and terminate on the oocyte plasma membrane at adhaerens type junctions (perhaps mixed with gap junctions). The possible functions and phylogenetic significance of such junctions are discussed.

Holland, ND, Campbell TG, Garey JR, Holland LZ, Wilson NG.  2009.  The Florida amphioxus (Cephalochordata) hosts larvae of the tapeworm Acanthobothrium brevissime: natural history, anatomy and taxonomic identification of the parasite. Acta Zoologica. 90:75-86.   10.1111/j.1463-6395.2008.00343.x   AbstractWebsite

Holland, N. D., Campbell, T. G., Garey, J. R., Holland, L. Z. and Wilson, N. G. 2009. The Florida amphioxus (Cephalochordata) hosts larvae of the tapeworm Acanthobothrium brevissime: natural history, anatomy and taxonomic identification of the parasite. - Acta Zoologica (Stockholm) 90: 75-86. Plerocercoid larvae of a tapeworm are frequently found in the hindgut lumen of the Florida amphioxus (Branchiostoma floridae) in central west Florida. About three-quarters of the adult amphioxus are parasitized. On average, each adult amphioxus hosts about five tapeworm larvae. The residence time of the parasites in the amphioxus gut appears to be in the order of several months, which is considerably shorter than the potential lifetime of the host. The living larvae range in length (when fully extended) from 300 to 850 mu m and are approximately cone-shaped, tapering to a point posteriorly and bearing a single large sucker anteriorly. Toward the anterior end of the body are four hookless bothridia, each indented by three loculi plus an inconspicuous accessory sucker. The larvae initiate the early stages of hook formation when they are cultured for a few days in urea-saline (mimicking the gut fluid of the definitive host, which is an elasmobranch). The tapeworm larvae are identifiable to genus and species on the basis of correspondences between their nuclear ribosomal DNA genes and those of adult specimens of Acanthobothrium brevissime recovered from the spiral valve of a stingray from the same environment.

Short, S, Kozmik Z, Holland LZ.  2012.  The Function and Developmental Expression of Alternatively Spliced Isoforms of Amphioxus and Xenopus laevis Pax2/5/8 Genes: Revealing Divergence at the Invertebrate to Vertebrate Transition . Journal of Experimental Zoology Part B-Molecular and Developmental Evolution. 318B(7):555-571.   10.1002/jez.b.22460  
Kreslova, J, Holland LZ, Schubert M, Burgtorf C, Benes V, Kozmik Z.  2002.  Functional equivalency of amphioxus and vertebrate Pax258 transcription factors suggests that the activation of mid-hindbrain specific genes in vertebrates occurs via the recruitment of Pax regulatory elements. Gene. 282:143-150.   10.1016/s0378-1119(01)00840-x   AbstractWebsite

Pax genes encode transcription factors that control key developmental decisions in various animal phyla. The Pax2/5/8 subfamily plays a key role in specification and/or maintenance of vertebrate mid-hindbrain boundary (MHB) region by directly regulating expression of other genes, most notably En2. In the invertebrate chordate amphioxus, expression of AmphiPax2/5/8 is found in many sites that are homologous to the regions of the vertebrate embryo expressing orthologous genes Pax2, Pax5 or Pax8. However, no co-expression of AmphiPax2/5/8 and AmphiEn is detected in the region of the neural tube that might correspond to the vertebrate MHB. Based on this observation and the absence of AmphiWnt expression in this region it appears that amphioxus does not have a MHB. Here we investigated the possibility that the AmphiPax2/5/8, as a key component of MHB development, has lost some of the properties of its vertebrate counterparts. We have analyzed both the DNA-binding and transactivation properties of AmphiPax2/5/8 as well as its ability to interact with the groucho co-repressor. In all these assays AmphiPax2/5/8 is indistinguishable from the human Pax5. In addition, we found two alternatively spliced AmphiPax2/5/8 isoforms that function similarly to the alternatively spliced isoforms of human Pax8. Analysis of the AmphiEn regulatory region provided no evidence for AmphiPax2/5/8 binding and transactivation. Therefore, in amphioxus, AmphiPax2/5/8, although capable of performing all the necessary functions has not been recruited for a developmental mechanism which usually sets up MHB development in vertebrates. (C) 2002 Elsevier Science B.V. All rights reserved.