MSGID: 1:317/3 64951fec   
   PID: hpt/lnx 1.9.0-cur 2019-01-08   
   TID: hpt/lnx 1.9.0-cur 2019-01-08   
    The clue is in the glue -- Nature's secret for holding it together   
      
      
     Date:   
         June 22, 2023   
     Source:   
         John Innes Centre   
     Summary:   
         An obscure aquatic plant has helped to explain how plants avoid   
         cracking up under the stresses and strains of growth.   
      
      
         Facebook Twitter Pinterest LinkedIN Email   
      
   ==========================================================================   
   FULL STORY   
   ==========================================================================   
   An obscure aquatic plant has helped to explain how plants avoid cracking   
   up under the stresses and strains of growth.   
      
   The finding by researchers Dr Robert Kelly-Bellow and Karen Lee in   
   the group of Professor Enrico Coen at the John Innes Centre, started   
   with a curious observation in a dwarf mutant of the carnivorous plant   
   Utricularia gibba.   
      
   The stems of this floating plant are filled with airspaces and this   
   hollowness means that the vascular column inside the stem can buckle   
   when under stress.   
      
   This effect would not be apparent in most plants, which have solid stems.   
      
   The researchers saw that in a dwarf mutant the central column was wavy   
   instead of straight. They hypothesised that this wobbly spine was caused   
   by an internal conflict, a disparity between what was happening inside the   
   plant stem and the epidermis or skin. Computational modelling by coauthor   
   Dr Richard Kennaway showed this idea could account for what was observed.   
      
   "We realized that in these types of dwarf, only the epidermis, the skin   
   of the stem, wants to be short, the internal tissue still wants to be   
   long hence the buckling effect," explains Professor Enrico Coen of the   
   John Innes Centre, an author of the study which appears in Science.   
      
   "This was a surprise -- previously people had thought that dwarf   
   varieties, which are very important in agriculture, would be dwarf   
   because everything in the stem is affected to grow less but in fact   
   it's just the skin in this case, creating a sort of straitjacket."   
   Further investigations revealed that the Utricularia gibba dwarf mutant   
   lacked a growth hormone called brassinosteroid.   
      
   They theorized that this hormone normally allows the skin to stretch,   
   giving a more forgiving straitjacket and allowing the plant stem to   
   elongate.   
      
   To test this idea, they used a mutant in the model plant Arabidopsis   
   that weakens the glue between cells, to see if reducing brassinosteroid   
   would cause major cracks to form in the skin of the stem as a result of   
   the stresses.   
      
   "That is exactly what we saw," explains Professor Coen. "Normally an   
   Arabidopsis stem with weakened glue will crack slightly because the   
   hormone is there to loosen the straitjacket. But when the hormone was   
   missing, the skin was completely ripped off and the plant was almost   
   skinless."  Computational modelling by coauthor Professor Richard Smith   
   showed brassinosteroid hormone was likely easing the straitjacket by   
   loosening fibres in the epidermal cell walls.   
      
   "Plant cells are stuck together and are forced to behave in a coordinated   
   way just by their pectin, their glue, that binds them. What we show in   
   this study is that this is an incredibly powerful force; the glue is so   
   strong you only need to change growth in one layer and the other cells   
   will follow," explains Professor Coen.   
      
   "Previous studies have emphasised that plants send molecular signals   
   to grow in a coordinated way, and this is still a part of the   
   explanation. But what our study shows is that the glueyness of plant   
   cells is also a vital component in coordinating growth. Sticking together   
   is very important."  Coauthor Dr Christopher Whitewoods at the Sainsbury   
   Laboratory, Cambridge University, emphasizes the potential importance of   
   these findings for future research. "The fact that mechanical interactions   
   between cell layers control growth in the stems of two wildly different   
   species raises the question of whether they control other aspects of   
   plant development, such as the complex internal patterning of leaves. We   
   are excited to test whether this is the case."  The findings shed light   
   on dwarfing varieties of crops, like wheat and rice, which underpin   
   agriculture's Green Revolution, explaining how genes control their growth   
   and how we might improve their efficiency in future.   
      
   Their findings also relate to developmental processes in animals, such   
   as formation of crocodile skin cracks and shaping of the intestine, where   
   mechanical interactions between layers are also thought to play a part.   
      
   Many hypotheses look promising to begin with but then fail to last the   
   full experimental course. Not so in this case, reflects Professor Coen.   
      
   "The first glimpse of the wobbly tissue in our dwarf aquatic plant was   
   exciting because as soon as we saw that, we had an idea of what might   
   be going on. But the biggest excitement came from testing the idea in   
   a completely different system.   
      
   "Nature is elusive. Ninety-nine percent of nice ideas fall flat on their   
   face when put to a critical test. But occasionally an idea survives   
   and you then know that nature has revealed one of its secrets to you,"   
   he says.   
      
   Brassinosteroid co-ordinates cell layer interactions in plants via cell   
   wall and tissue mechanics, appears in Science.   
      
       * RELATED_TOPICS   
             o Plants_&_Animals   
                   # Endangered_Plants # Botany #   
                   Biotechnology_and_Bioengineering # Genetics   
             o Earth_&_Climate   
                   # Ecology # Exotic_Species # Sustainability # Rainforests   
       * RELATED_TERMS   
             o Hydroponics o Seed o Plant_defense_against_being_eaten o   
             Water_hyacinth o Herbivore o Fertilizer o Plant_sexuality   
             o Botany   
      
   ==========================================================================   
   Story Source: Materials provided by John_Innes_Centre. Note: Content   
   may be edited for style and length.   
      
      
   ==========================================================================   
   Journal Reference:   
      1. Robert Kelly-Bellow, Karen Lee, Richard Kennaway, J. Elaine Barclay,   
         Annabel Whibley, Claire Bushell, Jamie Spooner, Man Yu, Paul Brett,   
         Baldeep Kular, Shujing Cheng, Jinfang Chu, Ting Xu, Brendan Lane,   
         James Fitzsimons, Yongbiao Xue, Richard S. Smith, Christopher   
         D. Whitewoods, Enrico Coen. Brassinosteroid coordinates cell layer   
         interactions in plants via cell wall and tissue mechanics. Science,   
         2023; 380 (6651): 1275 DOI: 10.1126/science.adf0752   
   ==========================================================================   
      
   Link to news story:   
   https://www.sciencedaily.com/releases/2023/06/230622142353.htm   
      
   --- up 1 year, 16 weeks, 3 days, 10 hours, 50 minutes   
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)   
   SEEN-BY: 15/0 106/201 114/705 123/120 153/7715 218/700 226/30 227/114   
   SEEN-BY: 229/110 112 113 307 317 400 426 428 470 664 700 291/111 292/854   
   SEEN-BY: 298/25 305/3 317/3 320/219 396/45 5075/35   
   PATH: 317/3 229/426