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"Kondensasi kromosom memainkan peran penting dalam pembelahan mitosis. Ion Ca2+ diketahui berperan penting dalam proses kondensasi kromosom. Sejauh ini, studi tentang peran Ca2+ dalam kromosom sel hewan telah dilaporkan melalui penggunaan 1,2-bis (2-aminophenoxyethane-N,N,N′,N-tetraacetic acid) (BAPTA) dan Ethylenediamine-tetraacetic acid (EDTA) sebagai agen pengkelat ion Ca2+. Namun, penelitian tentang peran Ca2+ pada kromosom tanaman masih sangat terbatas. Penelitian ini dilakukan untuk mengetahui pengaruh Ca2+ terhadap kromosom gandum (Triticum aestivum) dengan pemberian 1mM BAPTA sebagai agen pengkelat ion Ca2+, 1mM EDTA sebagai agen pengkelat kation divalen umum, dan phosphate buffered saline (PBS) sebagai kontrol menggunakan mikroskop cahaya. Preparasi kromosom dilakukan dengan cara akar gandum dipotong dan diberi perlakuan colchicine sebelum dilarutkan dalam 2% Paraformaldehyde (PFA). Kemudian diinkubasi dengan 2,5% selulase dan 2,5% enzim pectoliase pada suhu 37℃ selama 1 jam. Sampel kemudian disaring dan disentrifugasi untuk memperoleh sampel yang mengandung kromosom. Sampel kemudian diberi perlakuan dengan 1 mM BAPTA, 1 mM EDTA, dan PBS, dan diwarnai dengan Aceto orcein. Kromosom kemudian diamati di bawah mikroskop cahaya. Struktur dan kepadatan warna kromosom, serta panjang, lebar dan luas kromosom diamati dan diukur. Hasil pengamatan kualitatif menunjukkan bahwa struktur kromosom pada kontrol lebih rapat dan pendek sedangkan kromosom yang diberi perlakuan 1 mM BAPTA dan 1 mM EDTA mengalami dekondensasi, melebar, dan berwarna pucat. Hasil pengukuran kuantitatif menunjukkan bahwa kromosom Kontrol, BAPTA, dan EDTA masing-masing memiliki panjang 10.763 m, 14.845 m, 17.154 m, lebar 1.570 m, 1.637 m, 1.723 m, dan luas 18.172 m, 24.644 m, 29.687 M. Hasil uji statistik menunjukkan bahwa pengaruh BAPTA dan EDTA terhadap panjang dan luas kromosom berbeda nyata (α < 0,05). Hal ini membuktikan bahwa Ca2+ memiliki peran penting dalam menjaga struktur kromosom gandum.

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Chromosomal condensation plays an important role in the mitotic division. Ca2+ ions are known to play an important role in the chromosome condensation process. So far, studies on the role of Ca2+ in animal cell chromosomes have been reported using 1,2-bis (2-amino phenoxy ethane N, N, N′, N-tetraacetic acid) (BAPTA) and Ethylene diamine tetraacetic acid (EDTA) as Ca2+ ions chelating agents. However, research on the role of Ca2+ on plant chromosomes is still very limited. This study was conducted to determine the effect of Ca2+ on wheat chromosomes (Triticum aestivum) by administering 1mM BAPTA as a Ca2+ ion chelating agent, 1 mM EDTA as a general divalent cation chelating agent, and phosphate-buffered saline (PBS) as a control using a light microscope. For chromosome preparation, the root tips of wheat were cut and pretreated with colchicine before being dissolved in 2% Paraformaldehyde (PFA). The roots were then incubated with 2.5% cellulase and 2.5% pectoliase enzyme at 37℃ for 1hour. The sample is then filtered and centrifuged to obtain a sample containing chromosomes. Samples were then treated with 1 mM BAPTA, 1 mM EDTA, and PBS and stained with Aceto orcein. Chromosomes were then observed under a light microscope. The structure and color density of the chromosomes were observed. The length, width, and area of the chromosomes were also measured. The qualitative observations showed that the chromosome structure in control was denser and shorter while the chromosomes treated with 1 mM BAPTA and 1 mM EDTA were decondensed, widened, and had pale color. The quantitative measurement showed that length, width, and area of chromosomes for in control, BAPTA, and EDTA were 10.763 m, 14.845 m, 17.154 m; 1.570 m, 1.637 m, 1.723 m; and 18.172 m, 24.644 m, 29.687 M respectively. The statistical results showed that the effect of BAPTA and EDTA on the length and area of chromosomes were significantly different (α < 0.05). This result proves that Ca2+ has a vital role in maintaining the chromosomal structure of wheat."

"Kondensasi kromosom pada tahap metafase memiliki peranan penting dalam keberlangsungan siklus sel. Sejauh ini masih terus dilakukan penelitian mengenai faktor yang mempengaruhi kondensasi kromosom. Kation divalen, terutama kalsium (Ca2+) diketahui memiliki peranan penting dalam kondensasi kromosom manusia. Akan tetapi, peranan Ca2+ terhadap kromosom tumbuhan belum diketahui. Gandum merupakan salah satu organisme model dalam sitogenetika. Oleh karena itu, diperlukan penelitian mengenai efek Ca2+ kalsium terhadap kondensasi kromsosom gandum (Triticum spp.). Tujuan dari penelitian ini adalah untuk mengetahui pengaruh pemberian 1 mM BAPTA (1, 2-bis(2-aminophenoxy) ethane-N, N, N′, N′-tetraacetic acid), 1 mM EDTA (Ethylenediaminetetraacetic acid), sebagai pelekat Ca2+, terhadap struktur kromosom gandum menggunakan mikroskop cahaya dan Scanning Electron Microscope (SEM). Kecambah gandum dipotong bagian ujung akar dan diinkubasi di dalam larutan PFA (Paraformaldehyde) 2%. Sampel diinkubasi dengan enzim selulase 2,5 % dan pectoliase 2,5%. Setelah itu sampel diberi perlakuan masing-masing dengan 1 mM BAPTA, 1 mM EDTA, dan kontrol dengan PBS. Kromosom kemudian diwarnai dengan aceto orcein sedangkan yang diamati SEM dipreparasi melalui tahap fiksasi, post-fiksasi, staining, dehidrasi, dan dikeringkan dengan HMDS (hexamethyldisilazane) sebelum diamati menggunakan SEM. Hasil yang diperoleh pada pengamatan kuantitatif menunjukkan panjang rata-rata untuk kromosom kontrol 12,5±3,4 µm sedangkan pada perlakuan 1 mM BAPTA dan 1 mM EDTA panjang rata-rata yang diperoleh adalah 17,7±6,6 µm dan 41,9±16,3 µm. Struktur kromosom kontrol secara kualitatif lebih padat dan lebih terkondensasi. Akan tetapi kromosom yang diberi perlakuan 1 mM BAPTA dan 1 mM EDTA menunjukkan hasil yang lebih panjang, tersebar, dan terjadi dekondensasi kromosom sehingga serat-serat kromatin lebih terlihat jelas. Hal tersebut menunjukkan Ca2+ memiliki peranan penting dalam kondensasi kromosom gandum.

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Chromosome condensation at metaphase has an important role in the continuation of the cell cycle. Researches on the investigation of the major factors affecting chromosome condensation has been conducted so far. Divalent cations, especially Ca2+ has been reported to have an important role in human chromosome condensation. Nevertheless, its effect on the plant chromosome has yet to be evaluated. Wheat (Triticum spp.) is one of the model organisms in cytogenetics.Therefore, study to evaluate the effect of Ca2+ on wheat chromsosomes is required. The purpose of this study was to determine the effect of 1 mM BAPTA and 1 mM EDTA as the Ca2+ chelating agent on the wheat chromosomes using light microscope and SEM (Scanning Electron Microscope). The root tips of wheat sprouts was cut off and incubated in a 2% PFA (Paraformaldehyde)  solution. The sample was incubated with 2.5% cellulase and 2.5% pectoliase enzyme. After that, the samples were treated with 1 mM BAPTA, 1 mM EDTA, and PBS as control. Chromosome were then stained with aceto orcein, while sample for SEM were subjected to SEM preparation including fixation, post-fixtaion, staining, dehydration, and HMDS (hexamethyldisilazane)  drying. The results showed that the average length of the control chromosome was 12.5±3.4 µm, while those treated with 1 mM BAPTA and 1 mM EDTA showed the average length of 17.7 ± 6.6 µm and 41. 9 ± 16.3 µm, respectively. The qualitative observation of the control chromosomes showed the more compact and condensed structure. However, chromosomes treated with 1 mM BAPTA and 1 mM EDTA showed a longer, dispered, and decondensed chromosome showing the chromatin fibers. This result indicated that Ca2+ play an important role in wheat chromosome condensation."