Takashi Suyemitsu

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After the sea urchin embryo has developed to a pluteus larva, the adult rudiment (sea urchin rudiment) is formed, with other adult structures, on the left side of the larva and finally the juvenile sea urchin is formed after metamorphosis. We report here that thyroid hormones (THs) are involved in the formation of the adult rudiment and the adult-type(More)
The larva of the sand dollar Peronella japonica lacks a mouth and gut, and undergoes metamorphosis into a juvenile sand dollar without feeding. In the present study, it was found that thyroid hormones accelerate the metamorphosis of P. japonica larvae. The contents of thyroid hormones in larvae increased gradually during development. Thiourea and potassium(More)
The glycosaminoglycans (GAGs) of sperm and seminal plasma of normal men and seminal plasma of vasectomized individuals have been identified and quantified by two dimensional (2D) electrophoresis. The sperm contains predominantly CSC and HS as well as significant amounts of DS which achieves a high level in the sperm of the youngest man, while HA and LSC are(More)
Exogastrula-inducing peptides (EGIP) of the sea urchin Anthocidaris crassispina are endogenous peptides related to epidermal growth factor (EGF), which induce exogastrulation in the embryo. Recently, a protein(s) from sea urchin embryos that binds to one of the EGIP, EGIP-D (EGIP-D-binding protein, EBP) was purified. The isolation and characterization of(More)
In order to know the function of protein tyrosine kinases (PTKs) in the development of sea urchin embryos, we performed reverse transcription-polymerase chain reaction (RT-PCR) to obtain partial cDNA fragments for PTK genes using primers to highly conserved regions of the PTK family. A total of seven PTK sequences were identified, two of which represented(More)
The presence of sites specifically binding natural glucocortocoids in plasma membrane (PM) preparations (PM0, density=1.13-1.16; PM1, density=1.16-1.18) from rat liver was elucidated by equilibrium dialysis as well as by centrifugal methods. Equilibrium dialysis showed the presence of binding sites having a higher affinity for [3-H]cortisol (Kd=1.4 times(More)
The EGIP gene for exogastrula-inducing peptides (EGIPs) of the sea urchin Anthocidaris crassispina, which are structurally related to the epidermal growth factor, is activated at the onset of gastrulation in subdomains of the embryonic ectoderm. We showed in our previous study that the spatial and temporal regulation of EGIP is conducted by the upstream(More)
Four exogastrula-inducing peptides, A, B, C, and D have been isolated from the homogenates of embryos of the sea urchin, Anthocidaris crassispina, with successive chromatographic fractionations. The complete amino acid sequences of the peptides A and D were determined by analysis of the peptides generated by their digestion with lysyl endopeptidase. They(More)
Gossypol inhibited lactate dehydrogenase (LDH) noncompetitively in human spermatozoa. The inhibitory effect of gossypol on LDH was cancelled by the addition of human serum albumin, human gamma-globulin, bovine serum albumin or human seminal plasma. Seminal plasma was at least 10 times more effective than the other three proteins, when expressed on a per mg(More)