SEED ENVIRONMENTAL PERCEPTION AND ADAPTATION: CONTROL OF GENE EXPRESSION AND AUTOPHAGY MECHANISMS

Group Leader: Raquel Iglesias Fernández - Assistant Professor
This email address is being protected from spambots. You need JavaScript enabled to view it. 910679166 / 910679131 ( Lab 132 )

 

Personnel:

 

Seeds are the propagule selected by spermatophytes for dispersal and propagation of their lineage. The acquisition of tolerance to desiccation during maturation and the control of germination by dormancy are major adaptive traits that have contributed to making Spermatophytes one of the plant kingdom's most evolved creatures. From an agricultural point of view, seeds are the most important crop in the world and are the staple food for humans and domestic animals.


Irregular and incomplete seed germination is incompatible with modern agriculture. In the field, poor germination performance is aggravated by environmental fluctuations. The term "seed vigour" refers to the ability of a seed to germinate under a wide range of environmental conditions and represents a key milestone in food security. Despite the central importance of germination vigour, our molecular understanding of this process and its regulation remains rudimentary.


In our research group we approach the study of germination vigour from two perspectives:

  • Mechanisms related to gene expression: we study the transcriptional control of genes related to cell wall weakening (e.g., endo- β-mannanases) and their influence on seed germination. Similarly, we address global transcriptional changes associated with different stages of seed development (maturation and germination) in response to environmental fluctuations (e.g., temperature, salinity, drought). These studies are carried out in model species (Arabidopsis thaliana and Brachypodium distachyon) and in crops (Chenopodium quinoa, Hordeum vulgare, and Brassica rapa). This work aims to establish molecular markers associated with germination vigour.


 



(Images: Iglesias-Fernández et al. 2018. Frontiers in Plant Science. 10, pp.1706)

 

 

  • Autophagy in the seed: Autophagy is a catabolic process involved in the specific degradation of proteins in response to various stimuli. The autophagy in the seed is, to some extent, an unknown process. In our group, we address the study of autophagic mechanisms in (i) the accumulation of storage proteins during seed maturation and (ii) the reserve mobilisation during seed imbibition, as well as the selective protein degradation in response to environmental changes (temperature, salinity, and drought). To approach this, we use physiology, genetics, immunohistochemistry, and transcriptomics.

 

 

Figure 3: (A) Schematic representation of possible autophagy-like mechanisms in seeds. The Golgi-dependent pathway participates in the transport of DV, MVD, and PVC vesicles to the vacuole in a microautophagy-like mechanism during seed maturation. However, PAC and KDEL vesicles move from ER to PSV through the Golgi-independent route (also a microautophagy-like process). During seed imbibition, macroautophagy controls the expression of seed-specific transcription factors (ABI3, ABI4, and ABI5; ABA signalling) by a selective degradation mediated by ATG8 and a selective receptor (NBR1). Under unfavourable conditions, autophagy selective degradation ceases, thus inhibiting seed germination. DV: Dense Vesicle, MVB: Multivesicular Vesicle Body; PAC: Pre-Accumulating Vesicle, PSV: Protein Storage Vacuole; PVC: Pre-Vacuolar Compartment. Picture created with BioRender.com (https://biorender.com/). (B) Summary of the role of certain autophagic factors during seed development. Images illustrate a dicotyledonous seed from the globular stage during embryogenesis to germination. Sections are stained with naphthol blue-black (proteins in blue) and periodic acid plus Schiff´s reagent (insoluble polysaccharides in pink; R.I-F. contribution). ABA, GAs, and reserve levels are shown throughout seed development. ATG factors described as relevant in several aspects of seed development are indicated. C: Cotyledon; E: Embryo; R: Radicle.


(Imagen: Iglesias-Fernández and Vicente-Carbajosa, 2022, Pants, 11. pp. 3247)


Funding

  • Quinoa as a climate-smart crop diversification option for higher income generation from marginal lands in the Mediterranean (Quinoa4Med). PRIMA-EU program 2021 (Section 2) y Proyecto de Colaboración Internacional (ref.: PCI2022-132988).


                



  • “La quínoa como una nueva alternativa para el éxito en condiciones agrícolas marginales” (01/01/2020- 31/12/2021). Universidad Politécnica de Madrid-Banco Santander. Undergraduate thesis (UT, Biotechnology Degree) entitled "Physiological and molecular study of salt tolerance in Chenopodium quinoa seeds” presented by Lucía Martín Fernández: 1st award-UPM of the "III Premios Fin de Grado y Fin de Master para el Desarrollo para la Contribución al Cumplimiento de los Objetivos de Desarrollo Sostenible (ODS)” granted by the Vicerrectorado de Internacionalización (UPM). Award link and UT-link.

     

 

  • “Ingeniería de la pared celular en la planta modelo de cereales (Brachypodium distachyon) y en cebada (Hordeum vulgare)” -(INGE-CEREAL; Ref.: APOYO-JOVENES-MTOKUE-25-MKITFX). (01/03/2020- 31/03/2022). Comunidad de Madrid y Universidad Politécnica de Madrid.


     

 

  • “Estrés del retículo endoplásmico en plantas: nuevos componentes y aplicaciones biotecnológicas” (BIO2017-82873-R). (01/01/2018-31/12/2020). Ministerio de Ecomomía y Competitividad. (PI: Jesús Vicente Carbajosa; co-PI: Raquel Iglesias Fernández)


 

  • “Convocatoria de ayudas para la contratación de investigadores predoctorales e investigadores postdoctorales cofinanciadas por Fondo Social Europeo a través del Programa Operativo de Empleo Juvenil y la Iniciativa de Empleo Juvenil (YEI) 2018 de la Comunidad de Madrid” (PEJD-2018-PRE/BIO-8505). Comunidad de Madrid (01/02/2019-31/01/2020).


 

  • Development of epigenetic markers related to seed germination – (EPI-SEED: Ref.: VJIDOCUPM18ECB). (01/01/2018- 31/12/2019). UPM. Co-IPs: R. Iglesias-Fernández y E. Caro


 

 


Representative Publications

Iglesias-Fernández, R., Vicente-Carbajosa, J. 2022. A View into Seed Autophagy: From Development to Environmental Responses. Plants 11, 3247. DOI: 10.3390/plants11233247

Iglesias-Fernández, R., Pastor-Mora, E., Vicente-Carbajosa, J., Carbonero, P. 2020. A Possible Role of the Aleurone Expressed Gene HvMAN1 in the Hydrolysis of the Cell Wall Mannans of the Starchy Endosperm in Germinating Hordeum vulgare L. Seeds. Frontiers in Plant Science 10, 1706. DOI: 10.3389/fpls.2019.01706

Katsuya-Gaviria, K., Caro, E., Carrillo-Barral, N., Iglesias-Fernández, R. 2020. Reactive Oxygen Species (ROS) and Nucleic Acid Modifications During Seed Dormancy. Plants 9, 679. DOI: 10.3390/plants9060679

Carrillo-Barral, N., Matilla, A.J., Rodríguez-Gacio, M. del C., Iglesias-Fernández, R. 2018. Mannans and endo-β-mannanase transcripts are located in different seed compartments during Brassicaceae germination. Planta 247, 649–661. DOI: 10.1007/s00425-017-2815-4

Carbonero, P., Iglesias-Fernández, R., Vicente-Carbajosa, J. 2017. The AFL subfamily of B3 transcription factors: evolution and function in angiosperm seeds. Journal of Experimental Botany 68, 871–880. DOI: 10.1093/jxb/erw458

Willing, E.-M., Rawat, V., Mandáková, T., Maumus, F., James, G.V., Nordström, K.J.V., Becker, C., Warthmann, N., Chica, C., Szarzynska, B., Zytnicki, M., Albani, M.C., Kiefer, C., Bergonzi, S., Castaings, L., Mateos, J.L., Berns, M.C., Bujdoso, N., Piofczyk, T., de Lorenzo, L., Barrero-Sicilia, C., Mateos, I., Piednoël, M., Hagmann, J., Chen-Min-Tao, R., Iglesias-Fernández, R., Schuster, S.C., Alonso-Blanco, C., Roudier, F., Carbonero, P., Paz-Ares, J., Davis, S.J., Pecinka, A., Quesneville, H., Colot, V., Lysak, M.A., Weigel, D., Coupland, G., Schneeberger, K. 2015. Genome expansion of Arabis alpina linked with retrotransposition and reduced symmetric DNA methylation. Nature Plants 1, 1–7. DOI: 10.1038/nplants.2014.23

González-Calle, V., Barrero-Sicilia, C., Carbonero, P., Iglesias-Fernández, R. 2015. Mannans and endo-β-mannanases (MAN) in Brachypodium distachyon: expression profiling and possible role of the BdMAN genes during coleorhiza-limited seed germination. Journal of Experimental Botany 66, 3753–3764. DOI: 10.1093/jxb/erv168

Iglesias-Fernández, R., Barrero-Sicilia, C., Carrillo-Barral, N., Oñate-Sánchez, L., Carbonero, P. 2013. Arabidopsis thaliana bZIP44: a transcription factor affecting seed germination and expression of the mannanase-encoding gene AtMAN7. The Plant Journal 74, 767–780. DOI: 10.1111/tpj.12162

Rodríguez-Gacio, M. del C., Iglesias-Fernández, R., Carbonero, P., Matilla, Á.J. 2012. Softening-up mannan-rich cell walls. Journal of Experimental Botany 63, 3976–3988. DOI: 10.1093/jxb/ers096

Iglesias-Fernández, R., Rodríguez-Gacio, M.C., Barrero-Sicilia, C., Carbonero, P., Matilla, A. 2011. Three endo-β-mannanase genes expressed in the micropylar endosperm and in the radicle influence germination of Arabidopsis thaliana seeds. Planta 233, 25–36. DOI: 10.1007/s00425-010-1257-z

Iglesias-Fernández, R., Matilla, A.J. 2010. Genes involved in ethylene and gibberellins metabolism are required for endosperm-limited germination of Sisymbrium officinale L. seeds. Planta 231, 653–664. DOI: 10.1007/s00425-009-1073-5

Iglesias-Fernández, R., Matilla, A. 2009. After-ripening alters the gene expression pattern of oxidases involved in the ethylene and gibberellin pathways during early imbibition of Sisymbrium officinale L. seeds. Journal of Experimental Botany 60, 1645–1661. DOI: 10.1093/jxb/erp029