Divergent roles of the DEAD-box protein BS-PL10, the urochordate homologue of human DDX3 and DDX3Y proteins, in colony astogeny and ontogeny

Abstract

Proteins of the highly conserved PL-10 (Ded1P) subfamily of DEAD-box family, participate in a wide variety of biological functions. However, the entire spectrum of their functions in both vertebrates and invertebrates is still unknown. Here, we isolated the Botryllus schlosseri (Urochordata) homologue, BS-PL10, revealing its distributions and functions in ontogeny and colony astogeny. In botryllid ascidians, the colony grows by increasing the number of modular units (each called a zooid) through a whole colony synchronized and weekly cyclical astogenic budding process (blastogenesis). At the level of the colony, both BS-PL10 mRNA and its protein (

Botryllus schlosseri: A model ascidian for the study of asexual reproduction

“…Therefore, the four phases corresponded to the daily developmental condition of zooids and buds. These recurrent phases were applied to B. schlosseri as a staging method by researchers in the United States and Israel (Lauzon et al, 1996(Lauzon et al, , 2002Laird and Weissman, 2004;Rabinowitz and Rinkevich, 2004;Voskoboynik et al, 2004;Rosner et al, 2006). Despite its apparent simplicity, this method gives poor information on the developmental stages of the three related blastogenetic generations (for instance, phase A includes primary buds in Sabbadin's stages 6 and 7 and phase B includes secondary buds in Sabbadin's stages 2 and 3) and cannot document the rapid developmental changes of buds and irregularities in the synchronization of the three blastogenetic 7.…”

The involvement of three signal transduction pathways in botryllid ascidian astogeny, as revealed by expression patterns of representative genes

“…4G). These deformed bud tissues expressed high levels of BS-PL10 as do normal buds (Rosner et al, 2006). On day 6, the only 'healthy looking' tissues were the crescent-like BS-PL10 positive undifferentiated epithelial-like tissues, which resembled early differentiating secondary buds (Fig.…”

“…4). Treatment impacts were evaluated by observing the colonies under binocular stereomicroscopy or by immunohistochemical analyses with b-catenin or BS-PL10 antibodies (Rosner et al, 2006). BS-PL10 expression differentiated between bud tissues (high expression) and zooidal tissues (low expressions; Rosner et al, 2006).…”

“…Astogeny is controlled by a combination of genetically mediated developmental programs and environmental cues (Rinkevich, 2002;Sánchez and Lasker, 2003), allowing the formation of species-specific architecture through integrated, fixed and variable developmental pathways (Rinkevich, 2002;Shaish et al, 2007). The developmental homeostasis throughout astogeny, universally reflected by high fidelity in the setting of morphological structures (Pachut et al, 1991;Rinkevich, 2002;Sánchez and Lasker, 2003;Hughes, 2005;Rosner et al, 2006, Shaish et al, 2007Kuecken et al, 2011), is presumably controlled by a network of gene expressions and transcription factors. Developing such a functioning network should involve a complex temporal and spatial interplay of molecular cascades and cellular, chemical and mechanical stimuli.…”

Identification and characteristics of DDX3 gene in the earthworm, Perionyx excavatus

“…In the urochordates (i.e., Botryllus schlosseri) and in diverse invertebrate phyla (represented by model organisms such as: Drosophila, Hydra, Planaria), DDX3 proteins (termed also PL10) seem to be the ancestral forms of both mammalian DDX3X and DDX3Y proteins and are involved in developmental pathways, highly expressed in adult undifferentiated soma and germ cells and in some adult and embryo's differentiating tissues 7) . But the mechanistic and functional knowledge of DDX3 proteins is limited 8) .…”