title: High expression of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE coincides with initiation of various developmental pathways in in vitro culture of Trifolium nigrescens.
abstract: The aim of this study was to identify and examine the expression pattern of the ortholog of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE gene from Trifolium nigrescens (TnSERK) in embryogenic and non-regenerative cultures of immature cotyledonary-stage zygotic embryos (CsZEs). In the presence of 1-naphthaleneacetic acid and N(6)-[2-isopentenyl]-adenine, the CsZE regenerated embryoids directly and in a lengthy culture produced callus which was embryogenic or remained non-regenerative. As revealed by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), the TnSERK was expressed in both embryogenic and non-regenerative cultures, but the expression level was significantly higher in embryogenic ones. An in situ RNA hybridization assay revealed that the expression of TnSERK preceded the induction of cell division in explants, and then, it was maintained exclusively in actively dividing cells from which embryoids, embryo-like structures (ELSs), callus or tracheary elements were produced. However, the cells involved in different morphogenic events differed in intensity of hybridization signal which was the highest in embryogenic cells. The TnSERK was up-regulated during the development of embryoids, but in cotyledonary embryos, it was preferentially expressed in the regions of the apical meristems. The occurrence of morphological and anatomical abnormalities in embryoid development was preceded by a decline in TnSERK expression, and this coincided with the parenchymatization of the ground tissue in developing ELSs. TnSERK was also down-regulated during the maturation of parenchyma and xylem elements in CsZE and callus. Altogether, these data suggest the involvement of TnSERK in the induction of various developmental programs related to differentiation/transdifferentiation and totipotent state of cell(s).
authors: The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239, Kraków, Poland.
authors: Maria
authors: M
authors: Pilarska
authors: Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland.
authors: Przemysław
authors: P
authors: Malec
authors: Institute of Plant Genetics and Biotechnology, Slovak Academy of Sciences, Akademicka 2, 950-07, Nitra, Slovak Republic.
authors: Jan
authors: J
authors: Salaj
authors: Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Kraków, Poland.
authors: Filip
authors: F
authors: Bartnicki
authors: Department of Plant Cytology and Embryology, Institute of Botany, Jagiellonian University, Gronostajowa 9, 30-387, Kraków, Poland. robert.konieczny@uj.edu.pl.
authors: Robert
authors: R
authors: Konieczny
mesh_terms: D015536:Down-Regulation; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000166:cytology / Q000201:enzymology / Q000254:growth & development; D017422:Sequence Analysis, DNA; D029921:Trifolium / Q000166:cytology / Q000201:enzymology* / Q000254:growth & development
chemical_list: D010940:Plant Proteins; D012333:RNA, Messenger; D011494:Protein Kinases; C106294:SERK protein, plant
keywords: Differentiation; Gene expression; Pluripotency; Somatic embryogenesis; Totipotency; Transdifferentiation