The Arabidopsis thaliana Homeobox Gene ATHB12 Is Involved in Symptom Development Caused by Geminivirus Infection

BACKGROUND: Geminiviruses are single-stranded DNA viruses that infect a number of monocotyledonous and dicotyledonous plants. Arabidopsis is susceptible to infection with the Curtovirus, Beet severe curly top virus (BSCTV). Infection of Arabidopsis with BSCTV causes severe symptoms characterized by stunting, leaf curling, and the development of abnormal inflorescence and root structures. BSCTV-induced symptom development requires the virus-encoded C4 protein which is thought to interact with specific plant-host proteins and disrupt signaling pathways important for controlling cell division and development. Very little is known about the specific plant regulatory factors that participate in BSCTV-induced symptom development. This study was conducted to identify specific transcription factors that are induced by BSCTV infection. METHODOLOGY/PRINCIPAL FINDINGS: Arabidopsis plants were inoculated with BSCTV and the induction of specific transcription factors was monitored using quantitative real-time polymerase chain reaction assays. We found that the ATHB12 and ATHB7 genes, members of the homeodomain-leucine zipper family of transcription factors previously shown to be induced by abscisic acid and water stress, are induced in symptomatic tissues of Arabidopsis inoculated with BSCTV. ATHB12 expression is correlated with an array of morphological abnormalities including leaf curling, stunting, and callus-like structures in infected Arabidopsis. Inoculation of plants with a BSCTV mutant with a defective c4 gene failed to induce ATHB12. Transgenic plants expressing the BSCTV C4 gene exhibited increased ATHB12 expression whereas BSCTV-infected ATHB12 knock-down plants developed milder symptoms and had lower ATHB12 expression compared to the wild-type plants. Reporter gene studies demonstrated that the ATHB12 promoter was responsive to BSCTV infection and the highest expression levels were observed in symptomatic tissues where cell cycle genes also were induced. CONCLUSIONS/SIGNIFICANCE: These results suggest that ATHB7 and ATHB12 may play an important role in the activation of the abnormal cell division associated with symptom development during geminivirus infection

JJUNGANPARK-_APPLICATION_PLAN_OF_AI_in_PUBLIC_DATA (2) (2).docx

  Changes to approval criteria and QA/QC (combination of quality assurance) standards are sensitive issues to statistical data producers because the production of new national statistical data must be approved by the Office of National Statistics. Concerns about implementing AI and/or big data technology into national statistical data have been on the rise internationally. In other words, rapid changes to approval criteria for national statistical data are occurring in real-time. However, despite signs of institutional change, a stark contrast in methodology and evaluation standards between AI/big data technology and current statistical techniques indicates some form of resistance in actual implementation.  As such, this report introduces the matters mentioned above and actual application cases abroad and explicitly analyzes technological issues of implementing AI technology into national statistical data production, ultimately unearthing elements needed to accelerate the adoption of institutional policy change. Two determinants were identified as necessary for stimulating the implementation of AI and big data technology into national statistical data based on implications deduced from anticipated issues. </p

Effect of Fine Dust on the Acidity of Acid Rain in South Korea

This research paper contains suggestions on how environmental crises should be seen by governments and society, as well as serious are they. Moreover, this study provides reviewers guidance for regarding environmental crises especially acid rain, which are now significant societal issues.    From October 2021 to July 2022, the concentration of fine dust on the day before rain was recorded accordingly. After, we investigated the correlation of how the fine dust concentration of the day before affected PH level of each sample of acid rain was measured with the procedure of the experiment and the use of OAKIAN Digital PH Meter.</p

BSCTV-induced disease symptoms in <i>Arabidopsis</i>.

<p>BSCTV infection was accomplished by agroinoculation of the center of rosette leaves of 4-week old plants by pinpricking. (A) Mock-inoculated <i>Arabidopsis</i> developed normal flowers and siliques on the shoot tips. (B) Typical disease symptoms such as curling of shoot tips, siliques, and cauline leaves on BSCTV-infected inflorescences. Anthocyanin accumulated on stunted axillary buds or shoots with callus-like structures. (C) Stunted and curled inflorescence stems on a whole BSCTV-infected plant. (D) Magnified shoot tips with curved, swollen and callus-like structures.</p

Comparison of <i>ATHB12</i> gene expression in uninfected and BSCTV-infected <i>Arabidopsis</i> plants.

<p>(A) <i>ATHB12</i> gene expression in inflorescence shoot tips, leaves, inflorescence stems, and roots of uninfected <i>Arabidopsis</i>. (B) <i>ATHB12</i> gene expression in BSCTV-infected plants showing significant induction in symptomatic inflorescence shoot tips. (C) Time course of <i>ATHB12</i> accumulation in response to BSCTV infection using semi-quantitative PCR. The data shown in (A) and (B) represent the mean ± S.D. of three or four experiments. Different letters (Panel A) or * (Panel B) refer to significant differences between mean values as determined using a Tukey's Multiple Comparison Test (P<0.05).</p

Expression of <i>ATHB12</i> and <i>ATHB7</i> in plants infected with wild-type BSCTV or a BSCTV <i>c4</i> mutant.

<p>Quantitative RT-PCR was used to determine the relative expression levels of <i>ATHB12</i> in the inflorescence shoot tips of infected plants and mock-inoculated Col-O compared to the transcript levels observed in a transgenic line expressing BSCTV C4. Note that both <i>ATHB12</i> and <i>ATHB7</i> transcript levels are significantly induced by wild-type BSCTV whereas no significant induction was seen in plants inoculated with the <i>c4</i> mutant virus. Transgenic <i>Arabidopsis</i> that constitutively expressed BSCTV C4 exhibited significantly higher expression of <i>ATHB12</i> and <i>ATHB7</i> than wild-type mock inoculated plants. The data shown represent the mean ± S.D. of three or four experiments; different letters above the bars refer to significant differences between mean values as determined using a Tukey's Multiple Comparison Test (P<0.05).</p

Symptom severity and infectivity of BSCTV in the <i>ATHB12</i> KD and Ws-O.

a<p>Asymptomatic: Inoculated plants were indistinguishable from mock-inoculated plants and inflorescence bolts did not exhibit any abnormal structures.</p>b<p>Mild symptoms: Mild curling of inflorescence shoot tips and inflorescence bolt height was comparable to control plants.</p>c<p>Severe symptoms: Severe curling of bolts, malformed inflorescence structures, and severe stunting of plants.</p

Localization of GUS activity in <i>Arabidopsis</i> plants expressing <i>ATHB12</i> promoter-<i>gusA</i> fusion or <i>CDC2</i> promoter-<i>gusA</i> fusion constructs.

<p>(A) Diagram depicting the three <i>ATHB12</i> promoter fusions used for these studies. The positions of several specific known transcription binding sites are shown. (B) GUS staining of representative plants expressing the three <i>ATHB12</i> promoter-<i>gusA</i> fusions. Note that the p2.2 line showed systemic GUS staining throughout the seedlings, whereas the p1.6 and p0.3 lines only stained positive in the roots and cotyledons, respectively. Based on this result we utilized the p2.2 line for BSCTV infection studies. (C) GUS staining of BSCTV-infected plants. All infected plants had a high intensity of GUS staining in the symptomatic tissues in the inflorescence shoot tip where aberrant cell division was evident in response to BSCTV infection. (D) Comparison of <i>ATHB12</i> and <i>CDC2</i> promoter activity in BSCTV-infected plants. All infected plants showed significant GUS staining in the symptomatic inflorescence shoot tips, demonstrating a correlation of <i>ATHB12</i> induction with the activation of <i>CDC2</i>. The pBI101.1 line was used for a negative control in all studies and was always negative for GUS activity.</p