ESOPHAGEAL GLANDS AND THEIR SECRETION

Submitted to ; Dr. Hafiz Muhammad Atif

Submitted By ; Abdul Qadir (39),

Muhammad Hassan(47

ESOPHAGAEL GLANDS The most advanced adaptation for plant

parasitism by nematode the product of parasitism gene That are expressed in their esophageal gland cells

These parasitic product secreted through their stylet into host tissue to control the process of parasitism

nematode esophagus have

muscular metacarpus

pump chamber

Three active secretory gland cells ,one dorsal and two sub ventral in position

A cytoplasmic body of eachgland cell extends forward in the esophagus and end in storage cavity(ampulla)

This ampulla is connectedto the esophageal lumen(tube) by a valve

•The valve of the dorsal gland cell is located nearthe base of the stylet

•The valves of sub ventral gland cells is present on back of the metacorporal pump chamber and release secretions into the tube of the esophagus

Secretory proteins are synthesized in the nuclear region of the gland cell

And stored in membrane-bounded granules that are transport to the ampulla

The gland secretion is controlled by the nervous system.

The sub ventral glands are the most active during parasitism infective juvenile stage.

Dorsal gland cell for the development and maintenance of feeding sites. e.g. syncytia and giant cells

Esophageal gland secretion

These stylet secretions play a role in infection and parasitism of plants

The secreted products in the nematode esophageal gland cells are called as secretome (secreted proteins) of a parasite that helpful in parasitism .

STYLET SECRETION FUNCTION

•Penetration • migration through root tissue• modification of root cells as feeding cells• formation of feeding tubes• Digestion of host cell cytoplasm to facilitate nutrient acquisition by the nematode

PARASITISM OF A PLANT CELL The nematode inject esophageal gland secretion through stylet in the root cell of

susceptible plant

The stylet penetrates the cell wall but does not puncture the plasma membrane

secretion deposit outside the plasma membrane and perforate in the Cytoplasm

through pores

Where they interact with receptor and other host protien for organizing and maintenance of feeding cell and to form

feeding tube.

secreted product containing nuclear localization signals may be targeted to host cell nucleus to directly regulate change in

host gene expression

These gland secretion alter the morphological, physiological, and molecular changes in the recipient cells to enable them to function as a continuous source of nutrients for the nematode parasitic stages