Plants are exposed to a variety of external and endogenous stimuli that modulate their development and, in the case of agricultural crops, directly impact productivity by reducing yield. As sessile organisms, they rely on their ability to perceive, discriminate, and respond to stimuli, coordinating complex changes that allow them to optimize resource allocation for growth, reproduction, and defense. Plants respond to biotic and abiotic stresses by inducing the proteins required to cope with these conditions. Calcium acts as a second messenger capable of transducing a broad spectrum of environmental and hormonal stimuli. Calcium-dependent protein kinases (CDPKs) serve as calcium sensor-transducers that mediate responses to both biotic and abiotic stresses.

CDPKs are encoded by multigene families whose members differ in expression patterns, subcellular localization, kinetic properties, and substrate specificity—suggesting that each isoform plays a distinct role in calcium signal transduction. Genome analysis of Solanum phureja allowed us to infer that the CDPK family in the potato plant comprises 26 members distributed across 4 subgroups, alongside 2 CDPK-related kinases (CRKs).

Because potato is a staple crop critical for supporting a growing global population, considerable effort is focused on understanding and enhancing its yield potential. In particular, our group investigates the specific roles of CDPK isoforms in the potato plant’s response to late blight—caused by Phytophthora infestans—and soil salinity. Elucidating the function of these enzymes will enable their biotechnological manipulation to generate more resilient potato crops.

Group members

Publications

OmicIntegrator: A Simple and Versatile Tool for Meta-Analysis.
Gitman IFB, Grossi CEM, Arico DS, Mazzella MA, Ulloa RM. (2026)  Plants (Basel). 2026 Jan 22;15(2):334. doi: 10.3390/plants15020334. PMID: 41600141; PMCID: PMC12845079.

Methylobacterium as a key symbiont in plant-microbe interactions: Its ecological and agricultural significance.
Grossi CEM, Ulloa RM, Sahin N, Tani A. (2025)
Plant Biotechnology (Tokyo). 2025 Sep 25;42(3):229-241. doi: 10.5511/plantbiotechnology.25.0309a. PMID: 41181079; PMCID: PMC12573535.

Plant Growth-Promoting Abilities of Methylobacterium sp. 2A Involve Auxin-Mediated Regulation of the Root Architecture.
Grossi CEM, Tani A, Mori IC, Matsuura T, Ulloa RM (2024)
Plant, Cell and Environment. http://doi.org/10.1111/pce.15116

Unveiling the Secrets of Calcium-Dependent Proteins in Plant Growth-Promoting Rhizobacteria: An Abundance of Discoveries Awaits.
Agaras BC, Grossi CEM, Ulloa RM (2023)
Plants; 12(19):3398. https://doi.org/10.3390/plants12193398

Characterization of two group III potato CDPKs, StCDPK22 and StCDPK24, that contain three EF-Hand motifs in their CLDs
Sciorra MD, Fantino E, Grossi CEM, Ulloa RM (2021)
Plant Physiol Biochem. https://doi.org/10.1016/j.plaphy.2021.03.008

Calcium ‑ dependent protein kinase 2 plays a positive role in the salt stress response in potato
Grossi CEM, Santin F, Quintana SA, Fantino E, Ulloa RM (2021)
Plant Cell Rep. https://doi.org/10.1007/s00299-021-02676-7

Methylobacterium sp. 2A Is a Plant Growth-Promoting Rhizobacteria That Has the Potential to Improve Potato Crop Yield Under Adverse Conditions
Grossi CEM, Fantino E, Serral F, Zawoznik MS, Fernandez Do Porto DA, Ulloa RM (2020)
Front Plant Sci 11:1–15 . https://doi.org/10.3389/fpls.2020.00071

Optimization of recombinant maize CDKA;1 and CycD6;1 production in Escherichia coli by response surface methodology
Méndez AAE, Pena LB, Curto LM, Sciorra MD, Ulloa RM, Garza Aguilar SM, Vázquez Ramos JM, Gallego SM (2020)
Protein Expr Purif 165:105483 . https://doi.org/10.1016/j.pep.2019.105483

A fluorometric method for the assay of protein kinase activity
Rojas BE, Santin F, Ulloa RM, Iglesias AA, Figueroa CM (2018)
Anal Biochem 557:120–122 https://doi.org/10.1016/j.ab.2018.07.018

StCDPK3 Phosphorylates In Vitro Two Transcription Factors Involved in GA and ABA Signaling in Potato: StRSG1 and StABF1
Grandellis C, Fantino E, Muñiz García MN, Bialer MG, Santin F, Capiati DA, Ulloa RM (2016).
PLoS ONE 11(12): e0167389. doi:10.1371/journal. pone.0167389

Analysis of the potato calcium-dependent protein kinase family and characterization of StCDPK7, a member induced upon infection with Phytophthora infestans.
Fantino E, Segretin ME, Santin F, Mirkin FG, Ulloa RM.
Plant Cell Rep. 2017 Jul;36(7):1137-1157. doi: 10.1007/s00299-017-2144-x. Epub 2017 Apr 27.

Solanumtuberosum StCDPK1 is regulated by miR390 at the posttranscriptional level and phosphorylates the auxin efflux carrier StPIN4 in vitro, a potential downstream target in potato development.
Santin F, Bhogale S, Fantino E, Grandellis C, Banerjee AK, Ulloa RM. 2016.
Physiol Plant.

Transcript profiling reveals that cysteine protease inhibitors are up-regulated in tuber sprouts after extended darkness.
Grandellis C, Giammaria V, Fantino E, Cerrudo I, Bachmann S, Santin F, Ulloa, RM 2016.
Functional & Integrative Genomics, 1-20.

The novel Solanumtuberosum calcium dependent protein kinase, StCDPK3, is expressed in actively growing organs.
Grandellis, C, Giammaria V, Bialer M, Santin F, Lin T, Hannapel DJ, Ulloa RM. 2012.
Planta, 236, 1831-48.

Characterization of StABF1, a stress-responsive bZIP transcription factor from Solanumtuberosum L. that is phosphorylated by StCDPK2 in vitro.
MUNIZ GARCIA MN, Giammaria V, Grandellis C, Tellez-Inon MT, Ulloa RM, Capiati DA. 2012.
Planta, 235, 761-78.

StCDPK2 expression and activity reveal a highly responsive potato calcium-dependent protein kinase involved in light signalling.
Giammaria V, Grandellis C, Bachmann S, Gargantini PR, Feingold SE, BRYAN G, Ulloa RM. 2011.
Planta, 233, 593-609.

Genomic and functional characterization of StCDPK1.
Gargantini PR, Giammaria V, Grandellis C, Feingold SE, Maldonado S, Ulloa RM. 2009.
Plant MolBiol, 70, 153-72.

A mutant ankyrin protein kinase from Medicago sativa affects Arabidopsis adventitious roots.
Chinchilla D, Frugier F, Raices M, Merchan F, Giammaria V, Gargantini P, Gonzalez-Rizzo S, Crespi M, Ulloa R. 2008.
Functional Plant Biology, 35, 92-101.

A CDPK isoform participates in the regulation of nodule number in Medicagotruncatula.
Gargantini PR, Gonzalez-Rizzo S, Chinchilla D, Raices M, Giammaria V, Ulloa RM, Frugier F, Crespi MD. 2006.
Plant J, 48, 843-56.

Regulation of CDPK isoforms during tuber development.
Raices M, Gargantini PR, Chinchilla D, Crespi M, Tellez-Inon MT, Ulloa RM. 2003a.
Plant MolBiol, 52, 1011-24.

Sucrose increases calcium-dependent protein kinase and phosphatase activities in potato plants.
Raices M, Macintosh GC, Ulloa RM, Gargantini PR, Vozza NF, Tellez-Inon MT. 2003b.
Cell MolBiol (Noisy-le-grand), 49, 959-64.

StCDPK1 is expressed in potato stolon tips and is induced by high sucrose concentration.
Raices M, Ulloa RM, Macintosh GC, Crespi M, Tellez-Inon MT. 2003c.
J Exp Bot, 54, 2589-91.

A calcium-dependent protein kinase is systemically induced upon wounding in tomato plants.
Chico JM, Raices M, Tellez-Inon MT, Ulloa RM. 2002.
Plant Physiol, 128, 256-70.

Jasmonic acid affects plant morphology and calcium-dependent protein kinase expression and activity in Solanumtuberosum.
Ulloa RM, Raices M, Macintosh GC, Maldonado S, Tellez-Inon MT. 2002.
Physiol Plant, 115, 417-427.

Molecular characterization of StCDPK1, a calcium-dependent protein kinase from Solanumtuberosum that is induced at the onset of tuber development.
Raices M, Chico JM, Tellez-Inon MT, Ulloa RM. 2001.
Plant MolBiol, 46, 591-601.

Protein kinase activity in different stages of potato (Solanumtuberosum L.) microtuberization.
Ulloa RM, Macintosh GC, Melchiorre M, Mentaberry AN, Dallari P, Moriconi DN, Téllez-Iñón MT. 1997.
Plant Cell Reports, 16, 426-429.

Changes in Calcium-Dependent Protein Kinase Activity during in Vitro Tuberization in Potato.
Macintosh GC, Ulloa RM, Raices M, Tellez-Inon MT. 1996.
PlantPhysiol, 112, 1541-1550.

Open to Work

Undergraduate Thesis:

Salinity is one of the key environmental factors limiting crop productivity. Furthermore, environmental pollution caused by the excessive use of fungicides for disease control—coupled with the emergence of pathogen strains resistant to their active ingredients—has driven the search for low-ecological-impact alternatives. Plant growth-promoting bacteria (PGPB) could play an important role in both the salt stress response and pathogen biocontrol.

In our laboratory, we isolated a Gram-negative bacterium belonging to the genus Methylobacterium with promising biotechnological potential. Inoculation with this isolate in potato plants mitigated the effects of salinity and demonstrated biocontrol activity against P. infestans. Additionally, genome sequencing allowed us to identify genes involved in various metabolic pathways associated with its capacity to promote plant growth and control harmful crop microorganisms.

We aim to evaluate whether Methylobacterium sp. 2A can be utilized as a bioinoculant, which could have a significant impact on the agricultural sector. To this end, we propose studying its ability to colonize different plant species:

Tomato (dicot) and rice (monocot) plants grown under control and saline stress conditions will be inoculated with this isolate. We will analyze the ability of Methylobacterium sp. 2A to colonize roots and determine biometric parameters by comparing inoculated and non-inoculated plants.

Fundings and Research Grants

PICT Grant 2021-I-A-00440 (Scientific and Technological Research Projects): “Evaluation of the plant growth-promoting activity of the isolate Methylobacterium sp. 2A for its use as an inoculant in potato (Solanum tuberosum) crops. Analysis of the plant–PGPR interaction.”

PICT Grant 2014-3018 (Scientific and Technological Research Projects): “Evaluation of transgenic potato plants overexpressing CDPK isoforms regarding their tolerance to drought and Phytophthora infestans infection.”

UBACYT Grant 2013–2016: “Functional characterization of CDPKs in potato plants exposed to high salinity and Phytophthora infestans infection.”

PIP Grant 2013–2016 (Multi-Year Research Projects): “Functional analysis of light-induced phosphoprotein profiles in plants.”

Ex-Members

Lic. Iván Federico Berco Gitman
Doctoral Fellow – CONICET
ifgitman@gmail.com