Clamp connections are structures formed between two hyphal cells in certain fungi that help maintain the dikaryotic condition in each new cell. When a hyphal tip is ready to divide, a clamp arises and forms a hook between the two nuclei. Clamp connections are thought to function similarly to ascogenous hooks in Ascomycota fungi, though some argue this is due to convergent evolution. Dolipore septa are septal walls with a characteristic doughnut-like swelling near the central pore. They contain a perforated, membranous septal pore cap that likely allows some cellular components to pass between cells while retarding others.

1. CLAMP CONNECTIONS

2. Clamp Connection
● It operates to ensure the maintenance of the dikaryotic
condition in each new cell or compartment of the
secondary mycelium.
● Structure formed by two hyphal cells of certain fungi.
● Used to create genetic variation like croizer
mechanism of sexual reproduction.

3. ● When a binucleate hyphal tip is ready to divide, it
arises between the two nuclei and form a hook.

4. Mechanism of Clamp connection

5. Role of clamp connection in maintaining a
dikaryon

6. ● It is interesting to note that some mycologists have
likened these structures to the hooks of the ascogenous
hyphae in Ascomycota.

7. ● However, other mycologists have suggested that the
similarity is due to convergent evolution.

8. Dolipore Septum
● In some species, the septum wall simply tapers toward
the central pore while in others the septal wall near the
pore is thickened to form a characteristic dough nut
like or barrel- shaped swelling. This latter type of
septum is called a dolipore septum.

9. ● It is a dome- shaped, membranous structure referred to
here as the septal pore cap.
● The structure appears to consist of modified
endoplasmic reticulum and is an integral and
functional part of the septal apparatus.

11. ● Although the caps of some species appear as
continuous, non- porous structures, those of most
species are perforate.
● In some cases, the perforations are large and of
irregular size and spacing while in other cases they are
smaller and of regular size and spacing.

12. Functions of Doliopore Septum
● It is probably safe to say that its exact function remains
unclear.
● It would seem, however, that the pore cap acts as a
screen or sieve, possibly permitting the passage of
some cellular components from one cell to the next
while retarding others.
● Various ultrastructural and cytochemical changes also
have been reported in doliopore septa during
basidiocarp development.