replacement for 'applyTo' config of Ext.form.TextField in ExtJS 4.2.x

I get this problem when upgrading ExtJS form version 3.1.1 to 4.2.1.

In ExtJS 3.x, there is a config - 'applyTo' for Ext.form.TextField, with this config, I can create a TextField from an existing element, that is ExtJS will not create new html element and only change the existing element attributes to make it become a Ext.form.TextField component.

However in ExtJS 4.2.1, I can not find this config in the docs, and the compatible layer of 3 to 4 says to use 'renderTo' to replace it. But it seems that 'renderTo' create a new html element.

How can I get the same result in ExtJS 4.2.1?