Unravelling chloroplast protein quality control in plants


Pablo Pulido

"Talent Attraction" researcher



Research summary







Chloroplasts are the organelles that define plants. In plants, they are the unique sites of photosynthesis, the only significant mechanism of energy input into the biosphere. They also mediate numerous essential biosynthetic processes and contribute to many other functions including stress responses. As a result, correct chloroplast performance is absolutely indispensable for plant fitness and agriculture. Plants are sessile organisms that display an astonishing capacity to adapt to adverse conditions including heat, cold, drought, and salinity. However, prolonged exposure to environmental stress inevitably results in productivity losses. These challenging conditions for plant growth are highly relevant in the context of climate change and food security.

One of the main problems that stresses cause at molecular level is protein misfolding and aggregation. Recycling of damaged proteins is achieved by the action of molecular chaperones but, when recycling is not possible, toxic aggregated proteins have to be degraded by the action of proteases to avoid cellular damage. Chaperones and proteases act coordinately and constitute protein quality control (PQC) systems that are required for organismal survival. In our project, we address the characterization of the chloroplast proteostasis network. It is long known for instance that the chaperone HSP70 posttranslationally regulates important chloroplast processes such as photosynthesis. However, the precise molecular mechanisms of the chaperone action remain unresolved. Importantly, the specificity of HSP70 is driven by its DNAJ partners, adaptors that recognise unfolded substrates and transfer them to the chaperone for refolding. Thus, DNAJs are useful tools for plant editing. Besides, disrupted proteostasis results in protein aggregation inside chloroplasts triggering a chloroplast-to-nucleus retrograde signal that regulates the expression of nuclear genes encoding plastid-targeted chaperones. Ultimately, an essential hallmark of the project is to gain knowledge for rational engineering of chloroplast proteostasis and nuclear reprogramming that will assist to manipulate crops stress resistance.

pulido fig1

Figure Legend: Figure. Canonical and non-canonical DNAJ proteins in plants. A, Traditional balanced model for proteostasis. Unfolded or aggregated substrates are refolded by molecular chaperones or degraded by the action of proteases. B, Proposed model of distinct mechanisms of protection from aggregation by canonical (HSP70-dependent: A to C types) and non-canonical (HSP70-independent: D to F types) DNAJ proteins. C, Schematic depiction of characteristic domains of DNAJ proteins in plants: J-domain (required for HSP70’s interaction), zinc finger domain (involved in protein-protein interactions), and C-terminal domain (also performs task of interaction with substrates) (Pulido and Leister, 2018).


Pulidolab2022 Laboratory Members

Pablo Pulido Talent Attraction Researcher
Jorge Vicente Postdoctoral Researcher

NOTE! This site uses cookies and similar technologies.

If you continue browsing or do not change browser settings, we consider your acepptance for using. Learn more

I understand


A cookie is a text file that is stored on your computer or mobile device via a web server and only that server will be able to retrieve or read the contents of the cookie and allow the Web site remember browser preferences and navigate efficiently. Cookies make the interaction between the user and the website faster and easier.

General information

This Website uses cookies. Cookies are small text files generated by the web pages you visit, which contain the session data that can be useful later in the website. In this way this Web remembers information about your visit, which can facilitate your next visit and make the website more useful.

How do cookies?

Cookies can only store text, usually always anonymous and encrypted. No personal information is ever stored in a cookie, or can be associated with identified or identifiable person.

The data allow this website to keep your information between the pages, and also to discuss how to interact with the website. Cookies are safe because they can only store information that is put there by the browser, which is information the user entered in the browser or included in the page request. You can not run the code and can not be used to access your computer. If a website encrypts cookie data, only the website can read the information.

What types of cookies used?

The cookies used by this website can be distinguished by the following criteria:

1. Types of cookies as the entity that manages:

Depending on who the entity operating the computer or domain where cookies are sent and treat the data obtained, we can distinguish:

- Own cookies: are those that are sent to the user's terminal equipment from a computer or domain managed by the editor itself and from which provides the service requested by the user.

- Third party cookies: these are those that are sent to the user's terminal equipment from a machine or domain that is not managed by the publisher, but by another entity data is obtained through cookies.

In the event that the cookies are installed from a computer or domain managed by the editor itself but the information collected by these is managed by a third party can not be considered as party cookies.

2. Types of cookies as the length of time that remain active:

Depending on the length of time that remain active in the terminal equipment can be distinguished:

- Session cookies: cookies are a type designed to collect and store data while the user accesses a web page. Are usually used to store information that only worth preserving for the service requested by the user at any one time (eg a list of products purchased).

- Persistent cookies: cookies are a type of data which are stored in the terminal and can be accessed and treated for a period defined by the head of the cookie, and can range from a few minutes to several years.

3. Cookies types according to their purpose:

Depending on the purpose for which the data are processed through cookies, we can distinguish between:

- Technical cookies: these are those that allow the user to navigate through a web page or application platform and the use of different options or services it exist as, for example, control traffic and data communication, identify the session, access to restricted access parts, remember the elements of an order, make the buying process an order, make an application for registration or participation in an event, use security features while browsing store content for dissemination videos or sound or share content via social networks.

- Customization cookies: these are those that allow the user to access the service with some general characteristics based on a predefined set of criteria in the user terminal would eg language, the type of browser through which you access the service, the locale from which you access the service, etc.

- Analysis cookies: they are those that allow the responsible for them, monitoring and analyzing the behavior of users of the web sites that are linked. The information gathered through such cookies are used in measuring the activity of web sites, application or platform and for the profiling of user navigation of such sites, applications and platforms, in order to make improvements function data analysis how users use the service.

Management tool cookies

This Website uses Google Analytics.

Google Analytics is a free tool from Google that primarily allows website owners know how users interact with your website. Also, enable cookies in the domain of the site in which you are and uses a set of cookies called "__utma" and "__utmz" to collect information anonymously and reporting of website trends without identifying individual users..

For statistics of use of this website use cookies in order to know the level of recurrence of our visitors and more interesting content. This way we can concentrate our efforts on improving the most visited areas and make the user more easily find what they are looking for. On this site you can use the information from your visit for statistical evaluations and calculations anonymous data and to ensure the continuity of service or to make improvements to their websites. For more details, see the link below privacy policy [http://www.google.com/intl/en/policies/privacy/]

How to manage cookies on your computer: disabling and deleting cookies

All Internet browsers allow you to limit the behavior of a cookie or disable cookies within settings or browser settings. The steps for doing so are different for each browser, you can find instructions in the help menu of your browser.

If you decline the use of cookies, since it is possible thanks to the preferences menu of your browser or settings, reject, this website will continue to function properly without the use of the same.

Can you allow, block or delete cookies installed on your computer by setting your browser options installed on your computer:

- For more information about Internet Explorer click here.
- For more information on Chrome click here.
- For more information about Safari click here.
- For more information about Firefox click here.

Through your browser, you can also view the cookies that are on your computer, and delete them as you see fit. Cookies are text files, you can open and read the contents. The data within them is almost always encrypted with a numeric key corresponding to an Internet session so often has no meaning beyond the website who wrote it.

Informed consent

The use of this website on the other hand, implies that you paid your specific consent to the use of cookies, on the terms and conditions provided in this Cookies Policy, without prejudice to the measures of deactivation and removal of cookies that you can take, and mentioned in the previous section.