Arabidopsis Cyclin-Dependent Kinase Gene CDKG;2 is Involved in Organogenic Responses Induced in Vitro

Abstract

The Arabidopsis CDKG;2 gene encodes a putative cyclin-dependent Ser/Thr protein kinase of unknown biological function. This gene shows structural similarity to animal and human cyclin-dependent (PITSLRE) kinases. This study used the homozygous knockout cdkg;2 mutant based on T-DNA insertional line SALK_090262 to study the effect of mutation of the CDKG;2 gene on explant response and in vitro plant regeneration. For callus induction and proliferation, hypocotyls and cotyledons of 3-day-old seedlings of cdkg;2 and A. thaliana ecotype Col-0 were cultured on solid MS medium supplemented with 2,4-D (2 mg l ). The initiation time of callus and shoot induction differed between the mutant and control cultures. Shoot regeneration after callus transfer on MS + TDZ was delayed in cdkg;2 (31 days versus 7 days in Col-0). Shoots formed on callus derived from Col-0 hypocotyls but not on cotyledon-derived callus; in cdkg;2, shoots developed on both callus types. Mutant shoots did not form roots, regenerants were dwarfed, and inflorescences had small bud-like flowers with a reduced corolla and generative organs. Abnormalities observed during cdkg;2 organogenesis suggest a role of CDKG;2 as a regulator of adventitious root initiation.K Ke ey y w wo or rd ds s: : Arabidopsis thaliana cyclin-dependent kinases, CDKG;2 gene, callus formation, organogenesis.

The Arabidopsis Cdk1/Cdk2 homolog CDKA ;1 controls chromosome axis assembly during plant meiosis

“…Next to CDKA;1, CDKG has been implicated in meiosis by controlling synapsis at ambient but not low temperatures (Zheng et al, 2014). However, CDKG, which is related to human Cdk10, is likely involved in transcriptional and posttranscriptional control of gene expression and presumably does not control structural components of chromosomes directly (Doonan & Kitsios, 2009;Tank & Thaker, 2011;Huang et al, 2013;Zabicki et al, 2013).…”

Plant CDKs—Driving the Cell Cycle through Climate Change

“…CDKG has a recognized role in meiosis by acting on the pairing of homologous chromosomes and synapse completion, suggesting a mechanism to explain thermal sensitivity in male meiocytes; besides, CDKG acts in mRNA processing, particularly in alternative splicing [ 41 ]. The cdkg;2 homozygous knockout mutant (SALK_090262) showed delayed shoot regeneration compared to the Arabidopsis wild type, dwarfism, and did not develop roots, suggesting that CDKG;2 affects morphogenic responses in culture, probably in the root meristem formation [ 42 ].…”

NtCDKG;2, uma proteína multifuncional, relacionada aos processos de transcrição, processamento de RNA e organização do fuso acromático no ciclo celular de <i>Nicotiana tabacum</i>

“…Visando determinar em que momento a proteína AtCDKG;2 é requerida durante os eventos de organogênese e proliferação celular, foram analisados os processos de indução de calos e regeneração de plantas in vitro, utilizando calos de uma linhagem de A. thaliana com o gene AtCDKG;2 inativo (ŻABICKI et al, 2013). Os autores do trabalho demonstraram que os mutantes AtCDKG;2 apresentaram atraso e defeitos na organogênese.…”