A new view on plant cell.

Pres ently, two im por tant, closely re lated prob lems of mod ern plant bi ol ogy: the concept of the plant cell and a struc tural the ory of plant bi o log i cal or gani sa tion are un der in ten-sive dis cus sion. Our knowl edge about plant cell wall bi ol ogy has grown sig nif i cantly from the six ties of the 20th cen tury, when pro teins were iden ti fied by their en zy matic ac tiv ity in the intine of pollen grains and this plant cell wall was described for the first time as a 'liv ing and phys i-o log i cally ac tive struc ture'. The con tem po rary suc cess of the stud ies of plant cell wall ac tiv ity re sults from the use of new mo lec u lar techniques , in clud ing the anal y sis of trans gen ic plants, as well as the new views of re search ers on the role of the cell wall in the life of the plant cell and of whole plant body. Such an approach is more in spir ing and more im por tant for un der standing func tion ing of plants than a clas si cal one, where the cell wall con sid ered a 'dead' part of the cell, was com pletely neglected. To date, opin ions on the ques tion 'what is a plant cell ?' dif fer. The dif fer ence con cerns the ques tion whether the plant cell wall is a part of the cell (not only the pro toplast). The view that the cell wall is an in te gral, highly dynamic el e ment of the plant cell and of the plant body, in volved in a bi-directional flow of in for ma tion is at pres ent ver i fied by the data sup plied by nu mer ous ex per i men tal plant bi-ol o gists. Cell walls are pro duced by the cell protoplast and they form a struc tural and func tional con tin uum within the whole plant. The pa per of P. Wojtaszek on many as pects of ac tiv ity of the plant cell wall (some of his papers are cited in the pres ent re view) also supports the above view …