Larval spicules, cilia, and symmetry as remnants of indirect development in the direct developing sea urchin Heliocidaris erythrogramma
Article Abstract:
A study of larval skeleton expression and ciliated band arrangement in cultured nonfeeding larvae of the echinoid Heliocidaris erythrogramma reveals the presence of a larval skeleton. Examination of the larvae under polarized light reveals that the ciliated band is symmetrical on both sides and moves on to the larval side that forms the dorsal surface of the larva. Cells on both sides of the plane of the ciliated band exhibit asymmetry in their fates, and consequently, in their role in juvenile development.
Publication Name: Developmental Biology
Subject: Biological sciences
ISSN: 0012-1606
Year: 1995
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Temporal embryonic expression of the sea urchin early H1 gene is controlled by sequences immediately upstream and downstream of the TATA element
Article Abstract:
The temporal expression of the histone H1 gene during early embryogenesis was investigated. The minimal sequences required for proper expression include the TATA element, a conserved sequence CCCACGTACGCAA just upstream of the TATA element, an Inr element at the transcription start site, and an internal sequence in the leader region of the H1 transcript. The respective functions of these sequence units were determined. Apparently, they play a role in activation and probably repression of the gene.
Publication Name: Developmental Biology
Subject: Biological sciences
ISSN: 0012-1606
Year: 1993
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Functions for PS integrins in tissue adhesion, migration, and shape changes during early embryonic development in Drosophila
Article Abstract:
A study was conducted to examine the roles of alphaPS1, alphaPS2 and betaPS during gastrulation. Time-lapse videomicroscopy showed that PS integrins play various roles in cell adhesion, tissue formation, organization and migration. Aberrant expression of these integrins result to abnormalities in embryonic tissues. However, it was observed that not all molecules are required during the embryonic process to produce a phenotype.
Publication Name: Developmental Biology
Subject: Biological sciences
ISSN: 0012-1606
Year: 1995
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