Ora Hazak

Plants lead hidden lives un­der­ground. Their root tips pe­ne­tra­te the soil in search of va­lu­able nut­ri­ents. They detect vital re­sour­ces like water, ni­tro­gen, and phos­pha­te and “decide” whether it’s worth con­ti­nuing to grow in a par­ti­cu­lar di­rec­tion or whether it would be better to search el­se­whe­re. The plant’s bran­ching root system trans­ports water and nut­ri­ents to the above-ground parts of the plant, along with a large number of si­gna­ling mole­cu­les – che­mi­cal com­pounds that convey in­for­ma­ti­on between or within cells.

“Roots warn the leaves if there’s a de­fi­ci­en­cy of water or phos­pha­te in the soil so that they can adapt their growth ac­cord­in­gly,” says Pro­fes­sor Ora Hazak, a re­se­ar­cher at the In­sti­tu­te of Plant Biology and Bio­tech­no­lo­gy at the Uni­ver­si­ty of Münster, who studies the mole­cu­lar basis of this com­mu­ni­ca­ti­on. 

Ora Hazak can be un­ders­tood as an in­ter­pre­ter of signals. She de­ciphers the si­gna­ling within plant roots by using ad­van­ced mi­cro­sco­py, ge­ne­tics and phy­sio­lo­gi­cal assays that measure root growth, for example. Her primary in­te­rest lies in de­co­ding the si­gna­ling lan­guage of tomato plants – one of the most im­portant crops world­wi­de. She also plans to study potato plants, which are ge­ne­ti­cal­ly very similar to tomato. “The leaves and roots are in con­stant com­mu­ni­ca­ti­on, which is vital for the health of the plant,” says Hazak. The leaves also send mole­cu­lar signals to the roots, along with sugar, hor­mo­nes, and amino acids, sup­por­ting their growth. 

This form of plant com­mu­ni­ca­ti­on is based on small pep­ti­des – mole­cu­les made from short chains of amino acids. The signal pep­ti­des move from cell to cell and through the plant, so­me­ti­mes co­vering long di­stan­ces to reach the target cells. The re­cep­tors on the cell surface re­co­gni­ze the pep­ti­des and respond by in­itia­ting certain ac­tivi­ties inside the cells that promote fruit growth, for in­stan­ce. In 2022, Hazak’s group has iden­ti­fied the full re­per­toire of im­portant peptide genes in tomato plants that contain blue­prints for si­gna­ling pep­ti­des. Sci­en­tists only know the func­tions of a few of these. Re­cent­ly, Hazak found out which signal peptide is re­spon­si­ble for the de­ve­lop­ment and growth of the phloem, one of two vital nut­ri­ent pa­thways in plants.

“If we un­der­stand the un­der­ly­ing signal me­cha­nisms, we can op­ti­mi­ze crop plants for agri­cul­tu­re,” says Hazak. For in­stan­ce, if we un­der­stand the mole­cu­lar lan­guage used to help trans­port water and nut­ri­ents from the roots to the leaves and fruit, we can enhance this process to achieve better yields. And if we know which signals control the tran­spi­ra­ti­on process –through which the leaves release water while cap­tu­ring CO2 for pho­to­syn­the­sis– we can prevent tomato plants from losing so much water. “Then we would be able to adapt tomato plants better to drought and improve the ef­fi­ci­en­cy of hy­dro­po­nic tomato-growing systems that use water-based nut­ri­ent so­lu­ti­ons,” says Hazak. These are pres­sing chal­len­ges, par­ti­cu­lar­ly in view of the climate crisis.

For Ora Hazak, plants have always been a mystery that she’s wanted to solve. Even in her grand­mo­ther’s dacha in Ulan-Ude, in Russia, she used to marvel at the be­au­ti­ful tiger lilies and Mi­cha­el­mas daisies. As a 14-year-old at school in Kamensk-Uralsky, she en­rol­led in a biology cor­re­spon­dence course. On Sundays, she would battle her way through the snow in tem­pe­ra­tures of minus 25 degrees Celsius to reach the public library so she could answer all the ques­ti­ons that came in a thick en­ve­lo­pe from the Uni­ver­si­ty of Moscow every two or three months. “There were books about plants that you weren’t allowed to borrow,” she recalls. She im­mer­sed herself in ques­ti­ons of plant ge­ne­tics – RNA, DNA, and stem cells – and started some hy­bri­di­za­ti­on ex­pe­ri­ments of her own. “I crossed dif­fe­rent colors of garden balsam. One of the re­sul­ting plants had a tiger pattern and a speck­led stem – I thought it was very be­au­ti­ful.”

Hazak was pre­desti­ned to go into plant re­se­arch. Her Jewish roots meant that she was able to study biology at the Uni­ver­si­ty of Tel Aviv, which is re­now­ned for its mole­cu­lar plant re­se­arch. After stints in Lau­sanne and Fri­bourg, she moved to Münster in January 2025. In her brand-new lab, she plans to find out more about the mole­cu­lar si­gna­ling lan­guage of plants. Among other things, she hopes to dis­co­ver which signal pep­ti­des are ac­tiva­ted when tomato plants are sub­jec­ted to stress, for in­stan­ce if they are de­pri­ved of iron or ex­pe­ri­en­cing osmotic stress due to the lack of water, for example during droughts. To re­se­arch this, her team is cul­ti­vat­ing the plants in hy­dro­po­nic systems and mo­di­fy­ing their DNA. Hazak is also in­ves­ti­ga­ting the signal mole­cu­les for sugar trans­port in to­matoes and pota­toes. “We are hoping to develop trail­bla­zing in­no­va­tions that will make plants more re­si­li­ent, pro­duc­tive, or vi­go­rous,” says Hazak. “And we hope to dis­co­ver new me­cha­nisms that plants use to adapt to the en­vi­ron­ment and to re­gu­la­te their growth.”

Alt­hough the cul­ti­va­ti­on of ge­ne­ti­cal­ly mo­di­fied plants is largely pro­hi­bi­ted in the Eu­ropean Union, an al­ter­na­ti­ve could be to ma­nu­fac­tu­re ar­ti­fi­ci­al pep­ti­des that make the plant cells carry out desired ac­tivi­ties. “For in­stan­ce, you could coat seeds with the peptide,” says Hazak, “and when the plant ger­mi­na­tes, it will receive a growth boost or better pro­tec­tion against water loss.” 

She also sees plants that have been ge­ne­ti­cal­ly mo­di­fied using the CRISPR/Cas gene scis­sors as part of a re­si­li­ent future for agri­cul­tu­re in which fewer people will go hungry. “Many people are skep­ti­cal about ge­ne­ti­cal­ly mo­di­fied plants,” she says, “but random mu­ta­ti­ons happen all the time in nature – in re­spon­se to UV ra­dia­ti­on, for in­stan­ce. In the lab we can ac­ce­le­ra­te this process dra­ma­ti­cal­ly and control it pre­cise­ly. I hope that le­gis­la­tors will soon re­co­gni­ze the po­ten­ti­al that this tech­no­lo­gy offers to over­co­me pres­sing agri­cul­tu­ral chal­len­ges.”

Hazak also sees her new re­se­arch group at the Uni­ver­si­ty of Münster as an in­cu­ba­tor for a new ge­nera­ti­on of sci­en­tists in the field of cel­lu­lar com­mu­ni­ca­ti­on in plants, who will one day conduct their own re­se­arch in la­bo­ra­to­ries scat­te­red all over the world. It is im­portant for her that her team members receive first-class trai­ning so that they can con­tri­bu­te to the in­ter­na­tio­nal plant re­se­arch network from which she herself has be­ne­fi­ted. This is the network that took her to Switz­er­land and has now brought her to Münster. For Hazak, this is also a per­so­nal peace project: “As re­se­ar­chers, we can’t end wars, but we can turn at­ten­ti­on from global con­flic­ts and focus on working more closely tog­e­ther and achie­ving so­me­thing po­si­ti­ve.”