title: RAP2.4a Is Transported through the Phloem to Regulate Cold and Heat Tolerance in Papaya Tree (Carica papaya cv. Maradol): Implications for Protection Against Abiotic Stress.
abstract: Plants respond to stress through metabolic and morphological changes that increase their ability to survive and grow. To this end, several transcription factor families are responsible for transmitting the signals that are required for these changes. Here, we studied the transcription factor superfamily AP2/ERF, particularly, RAP2.4 from Carica papaya cv. Maradol. We isolated four genes (CpRap2.4a, CpRAap2.4b, CpRap2.1 and CpRap2.10), and an in silico analysis showed that the four genes encode proteins that contain a conserved APETALA2 (AP2) domain located within group I and II transcription factors of the AP2/ERF superfamily. Semiquantitative PCR experiments indicated that each CpRap2 gene is differentially expressed under stress conditions, such as extreme temperatures. Moreover, genetic transformants of tobacco plants overexpressing CpRap2.4a and CpRap2.4b genes show a high level of tolerance to cold and heat stress compared to non-transformed plants. Confocal microscopy analysis of tobacco transgenic plants showed that CpRAP2.4a and CpRAP2.4b proteins were mainly localized to the nuclei of cells from the leaves and roots and also in the sieve elements. Moreover, the movement of CpRap2.4a RNA in tobacco grafting was analyzed. Our results indicate that CpRap2.4a and CpRap2.4b RNA in the papaya tree have a functional role in the response to stress conditions such as exposure to extreme temperatures via direct translation outside the parental RNA cell.
authors.affiliation: Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Luis
authors.initials: L
authors.lastname: Figueroa-Yañez
authors.affiliation: Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Pereira-Santana
authors.affiliation: Laboratorio de Farmacología, Facultad de Química, Universidad Autónoma de Yucatán, Mérida, Yucatán, México.
authors.forename: Ana
authors.initials: A
authors.lastname: Arroyo-Herrera
authors.affiliation: Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Ulises
authors.initials: U
authors.lastname: Rodriguez-Corona
authors.affiliation: Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Felipe
authors.initials: F
authors.lastname: Sanchez-Teyer
authors.affiliation: Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Jorge
authors.initials: J
authors.lastname: Espadas-Alcocer
authors.affiliation: Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Francisco
authors.initials: F
authors.lastname: Espadas-Gil
authors.affiliation: Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Felipe
authors.initials: F
authors.lastname: Barredo-Pool
authors.affiliation: Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Enrique
authors.initials: E
authors.lastname: Castaño
authors.affiliation: Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, México.
authors.forename: Luis Carlos
authors.initials: LC
authors.lastname: Rodriguez-Zapata
mesh_terms: D029441:Carica / Q000502:physiology*; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D003080:Cold Temperature; D018506:Gene Expression Regulation, Plant; D006358:Hot Temperature; D052585:Phloem / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000254:growth & development; D013312:Stress, Physiological; D014026:Nicotiana / Q000235:genetics / Q000254:growth & development; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors