理工学部

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.

Books and Other Publications

 4

Presentations

 51

Research Projects

 17

Social Activities

 1