start-ver=1.4
cd-journal=joma
no-vol=6
cd-vols=
no-issue=1
article-no=
start-page=53
end-page=64
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=1999
dt-pub=1999
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=ライムギ小型染色体を保持する普通系コムギからのライムギ型cDNAのディファレンシャルスクリーニング
kn-title=Differential Screening of Rye-type cDNAs from a Common Wheat Carrying the Rye Midget Chromosomes
en-subtitle=
kn-subtitle=
en-abstract=ライムギの細胞質を有する普通系コムギ(cereale)-Chinese Spring (CS)には、「ミジェット」と呼ばれる非常に小型の染色体が存在する。この染色体が失われると、その種子は胚乳が退化して発芽出来ない。かりに発芽しても、その植物は虚弱で不稔となる。このことは、この染色体にライムギ細胞質の機能維持に不可欠な遺伝子が座乗していることを示唆している。本研究では、ディファレンシャルスクリーニング法により、このミジェット染色体に座乗している遺伝子の同定を試みた。(cereale)-CSの若苗からcDNAライブラリーを作成し、約20,000のプラークをスクリーニングした。その結果、ライムギのcDNAには強くハイブリダイズするが、CSのcDNAには弱くハイブリダイズするクローンが27得られた。これらについてその特異性をサザンハイブリダイゼイション等で解析したところ、19個のクローン(
CrClAなど) はサイズ、制限酵素部位に違いは認められるもののお互いにハイブリダイズすることから、同じクラス�Tに分類された。これらは、正常CSと(cereale)-CSとの間でRELP（制限酵素断片長多型）を示し、その型はライムギと同様であった。このcDNAの塩基配列は、コムギ葉緑体DNA遺伝子rbcLに類似しており、ライムギの葉緑体DNAに由来していると考えられた。他のクローンは、コムギの核遺伝子cabとrbcにその塩基配列が類似していたが、はっきりとした多型は検出されなかった。ここで用いた方法では、光合成に関連した発現量の多いcDNAがスクリーニングされやすい傾向があり、効率的なスクリーニングには均一化したcDNAを用いる必要があると思われる。
kn-abstract=Occurrence of the midget chromosome in a common wheat with rye cytoplasm [(cereale)-Chinese Spring (CS)] indicates that the chromosome carries the essential gene(s) for maintaining the function of rye cytoplasm. To elucidate the interaction between the midget chromosome and rye cytoplasm, in this study, an attempt was made to isolate rye-type cDNAs from a cDNA library of (cereale)-CS by differential screening. Two replica filters from each plate were hybridized with digoxigenin (DIG)-labeled wheat CS cDNAs and with DIG-labeled rye cDNAs,respectively. Out of ca. 20,000 plaques, 27 were hybridized more strongly with rye cDNAs than with CS cDNAs. These clones were classified into six classes (�T-�Y) by blot hybridization. The majority of the clones (21 out of 27) was belonged to the same class (1), showing rye-type RFLP (restriction fragment length polymorphism). The DNA sequence of clone CrClA in class �T, was very similar to that of wheat ribulose 1,5-bisphosphate carboxylase,large subnit gene, rbcL(94.5% homology). However, the 3' end of CrClA was shorter than that of wheat rbcL, and terminated at TAA instead of TAG, like the rbcL of Aegilops crassa. In the clone CrC5.4, the first half of the sequence was similar to that of one rice EST clone, the functions of which are not known, and the latter was similar to the reverse sequence of maize 4.5S-23S ribosomal RNA. This suggests that CrC5.4 had been derived from two defferent cDNAs of (cereale)-CS. Three other clones had homology to the chlorophyll a/b binding protein genes (cab) of wheat, maize and tomato, and one to wheat rbcS (ribulose1,5-bisphosphate carboxylase small subnit gene). However, no clear polymorphisms were detected between wheat and rye by using those clones as probes.
en-copyright=
kn-copyright=

en-aut-name=MurataMinoru
en-aut-sei=Murata
en-aut-mei=Minoru
kn-aut-name=村田稔
kn-aut-sei=村田
kn-aut-mei=稔
aut-affil-num=1
ORCID=

affil-num=1
en-affil=
kn-affil=岡山大学
en-keyword=Cytoplasm substitution line
kn-keyword=Cytoplasm substitution line
en-keyword=Differential screening
kn-keyword=Differential screening
en-keyword=Midget chromosome
kn-keyword=Midget chromosome
en-keyword=Rye
kn-keyword=Rye
en-keyword=Wheat
kn-keyword=Wheat
END

start-ver=1.4
cd-journal=joma
no-vol=117
cd-vols=
no-issue=14
article-no=
start-page=2963
end-page=2970
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2004
dt-pub=20046
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Differential localization of the centromere-specific proteins in the major centromeric satellite of Arabidopsis thaliana
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=<p>The 180 bp family of tandem repetitive sequences, which constitutes the major centromeric satellite in Arabidopsis thaliana, is thought to play important roles in kinetochore assembly. To assess the centromere activities of the 180 bp repeats, we performed indirect fluorescence immunolabeling with antibodies against phosphorylated histone H3 at Serl0, HTR12 (Arabidopsis centromeric histone H3 variant) and AtCENP-C (Arabidopsis CENP-C homologue) for the A. thaliana cell cultures. The immunosignals from all three antibodies appeared on all sites of the 180 bp,repeats detected by fluorescence in situ hybridization. However, some of the 180 bp repeat clusters, particularly those that were long or stretched at interphase, were not fully covered with the signals from anti-HTR12 or AtCENP-C. Chromatin fiber immunolabeling clearly revealed that the centromeric proteins examined in this study, localize only at the knobs on the extended chromatin fibers, which form a limited part of the 180 bp clusters. Furthermore, outer HTR12 and inner phosphohistone H3 (Ser1O) localization at the kinetochores of metaphase chromosomes suggests that two kinds of histone H3 (a centromere variant and a phosphorylated form) might be linked to different roles in centromere functionality; the former for spindle-fiber attachment, and the latter for chromatid cohesion.</p>

en-copyright=
kn-copyright=

en-aut-name=ShibataFukashi
en-aut-sei=Shibata
en-aut-mei=Fukashi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=MurataMinoru
en-aut-sei=Murata
en-aut-mei=Minoru
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

affil-num=1
en-affil=
kn-affil=Japan Science and Technology, Kawaguchi

affil-num=2
en-affil=
kn-affil=Okayama  University
en-keyword=180 bp repeat
kn-keyword=180 bp repeat
en-keyword=Arabidopsis thaliana
kn-keyword=Arabidopsis thaliana
en-keyword=Centromere
kn-keyword=Centromere
en-keyword=proteins
kn-keyword=proteins
en-keyword=Histone H3
kn-keyword=Histone H3
en-keyword=Phosphorylation
kn-keyword=Phosphorylation
END