Curriculum Vitaes

Fujiwara Makoto

  (藤原 誠)

Profile Information

Affiliation
Associate Professor, Faculty of Science and Technology, Department of Materials and Life Sciences, Sophia University
Degree
Bachelor(The University of Tokyo)
Master(The University of Tokyo)
Ph. D.(The University of Tokyo)

Researcher number
90332345
J-GLOBAL ID
200901000526942076
researchmap Member ID
5000099166

1) Replication and morphology of plastids in Arabidopsis thaliana
2) Idioblast formation in Egeria densa

(Subject of research)
(1) Genetic control of plastid division.
(2) Cytological analysis of green algae.


Research Interests

 4

Papers

 56
  • Alvin Sanjaya, Ryo Nishijima, Yuki Fujii, Makoto Asano, Kotaro Ishii, Yusuke Kazama, Tomoko Abe, Makoto T. Fujiwara
    Frontiers in Plant Science, 15, Sep, 2024  Peer-reviewedLast authorCorresponding author
    Pre-mRNA splicing is a fundamental process in eukaryotic gene expression, and the mechanism of intron definition, involving the recognition of the canonical GU (5’-splice site) and AG (3’-splice site) dinucleotides by splicing factors, has been postulated for most cases of splicing initiation in plants. Splice site mutations have played crucial roles in unraveling the mechanism of pre-mRNA splicing in planta. Typically, splice site mutations abolish splicing events or activate one or more cryptic splice sites surrounding the mutated region. In this report, we investigated the splicing pattern of the EGY1 gene in an Ar-ion-induced egy1-4 allele of Arabidopsis thaliana. egy1-4 has an AG-to-AC mutation in the 3′-end of intron 3, along with 4-bp substitutions and a 5-bp deletion in adjacent exon 4. RT-PCR, cDNA cloning, and amplicon sequencing analyses of EGY1 revealed that while most wild-type EGY1 mRNAs had a single splicing pattern, egy1-4 mRNAs had multiple splicing defects. Almost half of EGY1 transcripts showed ‘intron retention’ at intron 3, while the other half exhibited activation of 3’ cryptic splice sites either upstream or downstream of the original 3’-splice site. Unexpectedly, around 8% of EGY1 transcripts in egy1-4 exhibited activation of cryptic 5′-splice sites positioned upstream of the authentic 5’-splice site of intron 3. Whole genome resequencing of egy1-4 indicated that it has no other known impactful mutations. These results may provide a rare, but real case of activation of cryptic 5’-splice sites by downstream 3’-splice site/exon mutations in planta.
  • Makoto T Fujiwara, Yasushi Yoshioka, Yusuke Kazama, Tomonari Hirano, Yasuo Niwa, Takashi Moriyama, Naoki Sato, Tomoko Abe, Shigeo Yoshida, Ryuuichi D Itoh
    Plant Physiology, Sep, 2024  Peer-reviewedLead authorCorresponding author
  • Kanae Matsuoka, Hiroko Kubotera, Rina Miyazaki, Shota Moriyama, Makoto T Fujiwara, Ryuuichi D Itoh
    International Journal of Plant Biology, Jan, 2024  Peer-reviewed
  • Akane Yamagishi, Yuki Egoshi, Makoto T Fujiwara, Noriyuki Suzuki, Tohru Taniguchi, Ryuuichi D Itoh, Yumiko Suzuki, Yoshiro Masuyama, Kenji Monde, Toyonobu Usuki
    CHEMISTRY – A EUROPEAN JOURNAL (Weinheim an der Bergstrasse, Germany), 29(8) e202203396, Feb 7, 2023  Peer-reviewedCorresponding author
    Foeniculoxin is a major phytotoxin produced by Italian strains of Phomopsis foeniculi. The first total synthesis is described utilizing the ene reaction and Sonogashira cross-coupling reaction as key steps. The absolute configuration of the C6' was determined using chiral separation and advanced Mosher's method. The phytotoxicity of the synthesized compound was demonstrated via syringe-based infiltration into Chenopodium album and Arabidopsis thaliana leaves. Synthetic foeniculoxin induced various defects in A. thaliana leaf cells before lesion formation, including protein leakage into the cytoplasm from both chloroplasts and mitochondria and mitochondrial rounding and swelling. Furthermore, foeniculoxin and the antibiotic hygromycin B caused similar agglomeration of mitochondria around chloroplasts, highlighting this event as a common component in the early stages of plant cell death.
  • Ryuuichi D. Itoh, Kohdai P. Nakajima, Shun Sasaki, Hiroki Ishikawa, Yusuke Kazama, Tomoko Abe, Makoto T. Fujiwara
    PLANT JOURNAL, 107(1) 237-255, Jul, 2021  Peer-reviewedLast author
    Stromules are dynamic membrane-bound tubular structures that emanate from plastids. Stromule formation is triggered in response to various stresses and during plant development, suggesting that stromules may have physiological and developmental roles in these processes. Despite the possible biological importance of stromules and their prevalence in green plants, their exact roles and formation mechanisms remain unclear. To explore these issues, we obtained Arabidopsis thaliana mutants with excess stromule formation in the leaf epidermis by microscopy-based screening. Here, we characterized one of these mutants, stromule biogenesis altered 1 (suba1). suba1 forms plastids with severely altered morphology in a variety of non-mesophyll tissues, such as leaf epidermis, hypocotyl epidermis, floral tissues, and pollen grains, but apparently normal leaf mesophyll chloroplasts. The suba1 mutation causes impaired chloroplast pigmentation and altered chloroplast ultrastructure in stomatal guard cells, as well as the aberrant accumulation of lipid droplets and their autophagic engulfment by the vacuole. The causal defective gene in suba1 is TRIGALACTOSYLDIACYLGLYCEROL5 (TGD5), which encodes a protein putatively involved in the endoplasmic reticulum (ER)-to-plastid lipid trafficking required for the ER pathway of thylakoid lipid assembly. These findings suggest that a non-mesophyll-specific mechanism maintains plastid morphology. The distinct mechanisms maintaining plastid morphology in mesophyll versus non-mesophyll plastids might be attributable, at least in part, to the differential contributions of the plastidial and ER pathways of lipid metabolism between mesophyll and non-mesophyll plastids.

Misc.

 9
  • Sanjaya A, Muramatsu R, Sato S, Suzuki M, Sasaki S, Ishikawa H, Fujii Y, Asano M, Itoh R, Kanamaru K, Ohbu S, Abe T, Kazama Y, Fujiwara M
    RIKEN Accelerator Progress Report, 55 S30, Dec, 2022  Peer-reviewed
  • Sanjaya A, Kazama Y, Ishii K, Ohbu S, Abe T, Fujiwara M
    RIKEN Accelerator Progress Report, 54 178, Oct, 2021  Peer-reviewed
  • Morita R, Nakagawa M, Takehisa H, Hayashi Y, Ichida H, Usuda S, Ichinose K, Abe H, Shirakawa Y, Sato T, Fujiwara M, Itoh R, Abe T
    RIKEN Accelerator Progress Report, 50 272-272, Oct, 2017  Peer-reviewed
  • Kazama Y, Fujiwara MT, Takehisa H, Ohbu S, Saito H, Ichida H, Hayashi Y, Abe T
    RIKEN Accelerator Progress Report, 46 264-264, Nov, 2013  Peer-reviewed
  • Fujiwara Makoto, Itoh Ryuuichi, Moriyama Takashi, Niwa Yasuo, Sato Naoki, Abe Tomoko, Yoshida Shigeo
    Plant and Cell Physiology Supplement, 2009 145-145, 2009  
    Amyloplasts are a differentiated form of plastids that serve for synthesis and storage of starch. Amyloplasts have double envelope membranes and divide by binary fission, as the leaf chloroplasts do. So far, research into the molecular mechanisms of plastid division has been conducted mainly using chloroplasts from leaf or algal cells. It remains unknown whether proliferation of non-photosynthetic plastids follows the 'chloroplast division model' in higher plants. In this study, we focus on the mechanisms of amyloplast proliferation in seed integuments of Arabidopsis. Using four chloroplast division mutants (arc5, arc6, minD and minE) and transgenic lines expressing stroma-targeted fluorescent proteins, we visualised and investigated amyloplast populations in outer ovule integument cells of the mutants. It was indicated that the control of amyloplast division is considerably different from that of chloroplasts.
  • Kazama Y, Saito H, Fujiwara M, Matsuyama T, Hayashi Y, Ryuto H, Fukunishi N, Abe T
    RIKEN Accelerator Progress Report, 41 225, Sep, 2008  Peer-reviewed
  • Fujiwara Makoto, Itoh Ryuuichi, Ishikawa Masayuki, Niwa Yasuo, Sato Naoki, Yoshida Shigeo, Abe Tomoko
    Plant and Cell Physiology Supplement, 2008 426-426, 2008  
    In vascular plants, non-photosynthetic plastids, such as amyloplasts for starch storage in tubers and root tips and leucoplasts referred to as non-coloured plastids in roots and other non-green tissues, are controlled by distinct mechanisms from those for leaf chloroplasts in terms of the structure and behaviour. To elucidate these issues, we constructed transgenic Arabidopsis plants, in which the N-terminal plastid targeting sequence from the plastid division factor AtFtsZ1-1 or the Rubisco small subunit is fused to the N-terminus of the green fluorescent protein or its variants and expressed stably under the control of the Cauliflower mosaic virus 35S promoter. By epifluorescence microscopy using living tissues of these plants, we found that leucoplasts in seed integuments take highly filamentous forms and also produce stromules at high frequency. Furthermore, leucoplasts at the onset of amyloplast differentiation were found to display amoeboid-like shape and motility, as revealed by time-lapse epifluorescence microscopy.
  • Fujiwara Makoto, Itoh Ryuuichi, Niwa Yasuo, Nakamura Ayako, Shimada Yukihisa, Mller Simon, Yoshida Shigeo, Sato Naoki
    Plant and Cell Physiology Supplement, 2005 174-174, 2005  
    Chloroplast division is mediated by the co-ordinated action of a prokaryote-derived division system(s) and a host eukaryote-derived membrane fission system(s). The prokaryotic division system involves two Min proteins, MinD and MinE, which control division site placement in bacterial cells. Recently, it was shown that an Arabidopsis homologue of MinE, AtMinE, is a conserved factor involved in chloroplast division, and that the accumulation and replication of chloroplasts 11 mutant in Arabidopsis is a loss-of-function mutant of AtMinD1, an Arabidopsis homologue of MinD.<br>In this study, we analysed morphological abnormalities of chloroplasts in developing and matured tissues of both arc11 and AtMinE1 transgenic plants. Both plants grew normally under standard laboratory conditions, but contained abnormal chloroplasts with respect to size and morphology in developing and matured leaf cells. Our recent results as well as previous observations indicated that both MinD and MinE proteins control division site placement in chloroplasts, like in bacteria.
  • A Nagashima, M Hanaoka, M Fujiwara, T Shikanai, K Kanamaru, H Takahashi, K Tanaka
    PLANT AND CELL PHYSIOLOGY, 45 S33-S33, 2004  
    The plastid genome contains more than one hundred genes and the expression is regulated depending on plastid types and environmental conditions. Sigma factors determine the specificity of the eubacteria-type plastid RNA polymerase (PEP), and the roles of sigma factors for chloroplast gene expression remain largely unknown. In this study, we analyzed the expression of the sigma factors (SIG1-6) under various stress conditions, and found that the SIG5 transcript was rapidly and drastically induced under various stresses conditions. Because this induction was well correlated with the activation of the light-responsive promoter (LRP) of psbD, and because the psbD-LRP activation was abolished in the newly identified sig5 mutant (sig5-2), we conclud that SIG5 is a stress-responsive sigma factor in Arabidopsis, and responsible for the psbD-LRP transcription. We also found that the restoration of PSII activity after high light irradiation was delayed in the sig5 mutant, suggesting roles of SIG5 under stress conditions.

Books and Other Publications

 4

Presentations

 51

Research Projects

 17

Social Activities

 1