title: Aminolevulinate synthase 2 mediates erythrocyte differentiation by regulating larval globin expression during Xenopus primary hematopoiesis.
abstract: Hemoglobin synthesis by erythrocytes continues throughout a vertebrate's lifetime. The mechanism of mammalian heme synthesis has been studied for many years; aminolevulinate synthase 2 (ALAS2), a heme synthetase, is associated with X-linked dominant protoporphyria in humans. Amphibian and mammalian blood cells differ, but little is known about amphibian embryonic hemoglobin synthesis. We investigated the function of the Xenopus alas2 gene (Xalas2) in primitive amphibian erythrocytes and found that it is first expressed in primitive erythroid cells before hemoglobin alpha 3 subunit (hba3) during primary hematopoiesis and in the posterior ventral blood islands at the tailbud stage. Xalas2 is not expressed during secondary hematopoiesis in the dorsal lateral plate. Hemoglobin was barely detectable by o-dianisidine staining and hba3 transcript levels decreased in Xalas2-knockdown embryos. These results suggest that Xalas2 might be able to synthesize hemoglobin during hematopoiesis and mediate erythrocyte differentiation by regulating hba3 expression in Xenopus laevis.
authors.affiliation: Graduate School of Life and Environmental Sciences, The University of Tsukuba, Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan; Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan.
authors.forename: Asako
authors.initials: A
authors.lastname: Ogawa-Otomo
authors.affiliation: Graduate School of Life and Environmental Sciences, The University of Tsukuba, Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan; Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kurisaki
authors.affiliation: Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan. Electronic address: yuzu-itou@aist.go.jp.
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Ito
mesh_terms: D000624:5-Aminolevulinate Synthetase / Q000378:metabolism*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D020134:Catalytic Domain; D002454:Cell Differentiation; D004912:Erythrocytes / Q000166:cytology* / Q000378:metabolism; D004920:Erythropoiesis; D018507:Gene Expression Regulation, Developmental; D055018:Hemangioblasts / Q000378:metabolism; D006418:Heme / Q000378:metabolism; D006454:Hemoglobins / Q000378:metabolism; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013234:Stem Cells / Q000166:cytology; D029867:Xenopus Proteins / Q000378:metabolism*; D014982:Xenopus laevis
chemical_list: D006454:Hemoglobins; D016376:Oligonucleotides, Antisense; D012333:RNA, Messenger; D029867:Xenopus Proteins; D006418:Heme; D000624:5-Aminolevulinate Synthetase
keywords: Erythrocyte; Hematopoiesis; Hemoglobin; Xalas2; Xenopus