Einstein in his book. Relativity: The Special snd General Theory. http://www.ibiblio.org/ebooks/Einstein/Einstein_Relativity.pdf writes, "the expression for energy" in the form $\frac{mc^2 +E_0}{\sqrt 1-v^2/c2}$ Where m is the rest mass. $mc^2$ is the "kinetic energy" of the rest mass. $E_0$ is the energy added to the body. (by adding photons, for instance.) Then the rest mass energy, $mc^2$, and added energy, $E_0$, is divided by $\sqrt 1-v^2/c2$ to account for the energy of the velocity. And that, i think, produces gravity. That is my expectation. Am I right?

I am no expert on this. I welcome criticism of this post. I think This energy is what is said to curve spacetime, or create gravity.

Relativistic mass, is calculated as $\frac{M_(rest)}{\sqrt 1-v^2/c2}$

I think that relativistic mass is gravitational, as is "aborbed energy".