Molecular Research on the Leaf color of Ornamental Kale

Abstract

Ornamental kale (Brassica oleracea L. var. acephala) is used as a cut flower, pot, and landscape plant due to its strikingly colored and shaped leaves and resistance to cold environmental conditions. Leaf color varies in ornamental kale and increases the potential of the species as an ornamental plant. In general, the outer leaves are in green, while the inner leaves is white, pink, red and purple. Leaf color may vary depending on the developmental stage of the plant and the environmental conditions. Low temperatures lead to the transition of the inner leaves from green to red, pink, or white and are considered as the plant’s adaptation to low temperatures. The major color pigments in plants are chlorophyll, carotenoids, and anthocyanins. Research is continuing to determine the genes and transcription factors that are involved in the biosynthetic pathways of color pigments and control leaf color in ornamental kale. The identification of the genes and their expression profiles are carried out at the transcriptomic level. Most recently, the utilization of CRISPR/Cas9 genome editing enabled to explore the functions of target genes related to leaf color in ornamental kale. Determining the molecular mechanism underlying leaf color is important for breeding studies aimed to develop novel ornamental kale varieties. In the present review, molecular studies on leaf color in ornamental kale is summarized.

Keywords

• Ornamental kale
• leaf color
• Brassica

Süs Lahanalarında Yaprak Rengine Yönelik Moleküler Araştırmalar

Öz

Süs lahanaları (Brassica oleracea L. var. acephala), çarpıcı renk ve şekillerde yaprakları ve soğuk koşullara dayanımı ile kesme çiçek, saksı ve peyzaj bitkisi olarak değerlendirilmektedir. Süs lahanalarında yaprak rengi çeşitlilik göstermekte ve bitkinin süs bitkisi olarak değerlendirilme potansiyelini artırmaktadır. Genel olarak dış yapraklar yeşil tonlarında olurken iç kısımda gelişen yapraklar beyaz, pembe, kırmızı, mor renklerdedir. Gelişme dönemine ve çevresel koşullara göre yaprak rengi farklılık gösterebilmektedir. İç yaprakların kırmızı, pembe, mor veya beyaza dönüşümünün düşük sıcaklıklar tarafından teşvik edildiği, bu yolla bitkinin düşük sıcaklığa adaptasyon gösterdiği bildirilmektedir. Bitkilerde başlıca renk pigmentleri klorofil, karotenoidler ve antosiyaninlerdir. Süs lahanalarında başta antosiyaninler olmak üzere renk pigmentlerinin sentez yollarında yer alan genlerin ve transkripsiyon faktörlerinin belirlenmesine yönelik araştırmalar sürdürülmektedir. İlgili genlerin tespitine yönelik gen haritalarının oluşturulması ile genomik düzeyde ve RNA dizi analizleri ve gen ifade analizleri ile transkriptomik düzeyde çalışmalar yürütülmektedir. Son yıllarda CRISPR/Cas9 genom düzenleme yöntemi kullanılarak yaprak rengi ile ilişkili genlerin fonksiyonları oluşturulan mutant bitkilerle incelenmekte ve bu tekniğin süs lahanalarında kullanım olanağı değerlendirilmektedir. Süs lahanalarında yaprak renginin genetik ve moleküler mekanizmasının belirlenmesi yeni çeşitlerin geliştirilmesine yönelik ıslah çalışmaları bakımından önem taşımaktadır. Sunulan çalışmada süs lahanalarında yaprak rengi ile ilgili moleküler düzeyde yürütülen araştırmalar literatür bilgileri ışığında değerlendirilmiştir.

Anahtar Kelimeler

• Süs lahanası
• yaprak rengi
• Brassica

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